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Javascript Select Options all at Once

Is it possible to update all options of a <select> element at once?
Depending on a prior option selected, I would like
<select name="area" id="area" size="1" style="width: 150px"></select>
to change to (or something similar depending on the option selected):
<select name="area" id="area" size="1" style="width: 150px">
<option selected="" disabled="">Select An Area/Resource</option>
<option value="1">cafe</option>
<option value="2">lounge</option>
<option value="3" disabled="">quiet area</option>
<option value="4">tables</option>
</select>
The block of options is actually stored in a variable as you see them here:
<option selected="" disabled="">Select An Area/Resource</option><option value="1">cafe</option><option value="2">lounge</option><option value="3" disabled="">quiet area</option><option value="4">tables</option>

Sure. It's just a matter of changing the .innerHTML of the select element.
const options = '<option selected="" disabled="">Select An Area/Resource</option><option value="1">cafe</option><option value="2">lounge</option><option value="3" disabled="">quiet area</option><option value="4">tables</option>';
const list = document.querySelector("select");
document.querySelector("input").addEventListener("click", function(){
list.innerHTML = list.innerHTML === "" ? options : "";
});
<input type="checkbox">check or uncheck to change the following list.<br>
<select name="area" id="area" size="1" style="width: 150px"></select>

how can i change the value of checkbox when i select a value from select input with js

i want to learn that when i select a value from select input how can i change the value of checkbox.
<input type="checkbox" name="id" value="" id="mycheckbox1">
<select name="cat-1" id="myselectbox1">
<option value="">Choose</option>
<option value="100">Value1</option>
<option value="200">Value2</option>
</select>

Why would you want to?
Anyway:
window.addEventListener("load", function() { // on page load
document.getElementById("myselectbox1").addEventListener("change", function() {
document.getElementById("mycheckbox1").value = this.value;
});
document.getElementById("mycheckbox1").addEventListener("change", function() {
console.log(this.value);
});
});
<input type="checkbox" name="id" value="" id="mycheckbox1">
<select name="cat-1" id="myselectbox1">
<option value="">Choose</option>
<option value="100">Value1</option>
<option value="200">Value2</option>
</select>

function updateCheckbox() {
var val = document.getElementById("myselectbox1").value;
document.getElementById("mycheckbox1").checked = true;
document.getElementById("mycheckbox1").value = val;
}
<input type="checkbox" name="id" value="" id="mycheckbox1">
<select onChange="updateCheckbox()" name="cat-1" id="myselectbox1">
<option selected disabled>Choose</option>
<option value="100">Value1</option>
<option value="200">Value2</option>
</select>

may i ask one more question
i changed my checkbox value if i have one more select input which id cat-2
how can i change name of cat-2 to chosen value of cat-1
For example;
if i choose value1 ( its value=100)
i want to change name of cat-2 to cat-100
```
<input type="checkbox" name="id" value="" id="mycheckbox1">
<select name="cat-1" id="myselectbox1">
<option value="">Choose</option>
<option value="100">Value1</option>
<option value="200">Value2</option>
</select>
<select name="cat-2" id="myselectbox2">
<option value="">Choose</option>
<option value="300">Value3</option>
<option value="400">Value4</option>
</select>
```

How can i disable my input and the content inside using a selected option

I have looked around and haven't found a solution to my problem, I am trying to learn javascript and jquery. what I want to learn is how can I do so when I select the option "none" the <input> and the data inside it, should be disabled.
this is my attempts:
First attempt link:http://jsfiddle.net/kmtLy705/7/
First attempt code: (Works with buttons)
<input disabled id="page_navigation1" type="number">
<button class="add">Add</button>
<button class="remove">Remove</button>
<select>
<option value="0" class="add" selected>None</option>
<option value="1" class="remove">select</option>
<option value="2" class="remove">select</option>
<option value="3" class="remove">select</option>
<option value="4" class="remove">select</option>
<option value="5" class="remove">select</option>
</select>
jquery
$('.add').click(function() {
$('#page_navigation1').attr('disabled', true)
});
$('.remove').click(function() {
$('#page_navigation1').removeAttr('disabled');
});
Now, this code works with buttons but I have tried countless ways to make it work with an option and haven't found a solution yet.
Second attempt link: http://jsfiddle.net/5u9pfot0/1/ this doesn't work at all but the idea was there (when val1 is selected then the input should be disabled)
Second attempt code:
<select id="selectid" name="selectname">
<option value="val1" id="valid1"> Val1 </option>
<option value="val2" id="valid2"> Val2 </option>
<option value="val3" id="valid3"> Val3 </option>
</select>
<input disabled id="page_navigation1" type="number">
jquery:
if (document.getElementById('selectid').value == "val1") {
$('#page_navigation1').attr('disabled', true)
}

I have modified your second approach just a little.
Try doing below:
function callthis()
{
if (document.getElementById('selectid').value == "val1") {
$('#page_navigation1').attr('disabled', true);
}
else
$('#page_navigation1').attr('disabled', false);
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<select id="selectid" name="selectname" onchange="callthis();">
<option default disabled>Choose one</option>
<option value="val1" id="valid1"> Val1 </option>
<option value="val2" id="valid2"> Val2 </option>
<option value="val3" id="valid3"> Val3 </option>
</select>
<input disabled id="page_navigation1" type="number">

Autoselect HTML hidden option value based on previous option

I have 2 select tags which come with the same option, male and female. One of the select, "age" is hidden.
<select name="gender">
<option value="1">Male</option>
<option value="2">Female</option>
</select>
<select name="age" style="display:none;">
<option value="12">Male</option>
<option value="18">Female</option>
</select>
When user select "male" in "gender", I wish the "age" will automatically select "male" as well. I expect the same thing as "female". How to achieve this through javascript?

You can attach an event change to your select gender and set the value of age on every change.
Note that both elements should be loaded with a default selected value for case that the end user do not select nothing and also check that it is better to move inline styling style="display:none;" to a separated css file.
Code:
var gender = document.getElementsByName('gender')[0],
age = document.getElementsByName('age')[0];
gender.addEventListener('change', function() {
age.value = (gender.value == 1) ? 12 : 18;
console.log('Gender:', gender.value);
console.log('Age:', age.value);
});
<select name="gender">
<option value="1">Male</option>
<option value="2">Female</option>
</select>
<select name="age" style="display:none;">
<option value="12">Male</option>
<option value="18">Female</option>
</select>

Here's an option using jQuery.
$(document).ready(function() {
$("#age").val("12");
$("#gender").change(function() {
var userselected = $(this).find(':selected').text();
if (userselected == "Male") {
$("#age").val("12");
} else {
$("#age").val("18");
}
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<select name="gender" id="gender">
<option value="1">Male</option>
<option value="2">Female</option>
</select>
<select name="age" style="display:inherit;" id="age">
<option value="12">Male</option>
<option value="18">Female</option>
</select>

Jquery validate and a list of select box

How Can i specific require and unique condition for a list of select box like below?
<form name="signupForm" class="cmxform" id="signupForm" method="get" action="">
<select name="category[]" id="cat_1">
<option value="">Select One</option>
<option value="1">aa</option>
<option value="2">bb</option>
<option value="3">cc</option>
<option value="4">dd</option>
</select>
<select name="category[]" id="cat_2">
<option value="">Select One</option>
<option value="5">ee</option>
<option value="6">ff</option>
<option value="7">gg</option>
<option value="8">hh</option>
</select>
<select name="category[]" id="cat_3">
<option value="">Select One</option>
<option value="9">ii</option>
<option value="10">jj</option>
<option value="11">kk</option>
<option value="12">ll</option>
</select>
<input class="submit" type="submit" value="Submit">
</form>
Notice that there are the number of cat is not fixed, it can be more than 3,
so how to make it required for each selectbox,
and each selectbox chosen value must be unique using jquery validate plugin? Thank you

var $selects = $('form select[name^=category]'),
values = [];
$(':submit').click(function(e) {
e.preventDefault();
values = [];
$($selects).each(function() {
if($(this).val()) {
values.push($(this).val());
}
});
if(!values.length) {
alert('Please select all categories');
return false;
}
if(values.length < $selects.length || $.unique(values).length < $selects.length) {
alert('Please select all categories and be unique');
return false;
}
});
DEMO

Here is a great jQuery validation plugin that will make your life easier: http://www.position-absolute.com/articles/jquery-form-validator-because-form-validation-is-a-mess/
This is all you need to do: (the plugin does the rest)
<select id="sport" class="validate[required]" name="sport">
<option value="">--Select--</option>
<option value="option1">Tennis</option>
<option value="option2">Football</option>
<option value="option3">Golf</option>
</select>
Hope that helps :)