JSFiddle - React, Tailwind, and code Playground

HTML

<p>Select variable value below:</p>
<div>
    <form name="form001">
        <select name="choice">
            <option value="1">1</option>
            <option value="2">2</option>
            <option value="3">3</option>
        </select>
    </form>
</div>
        
<p id="selection"></p>

CSS

div, p {
    margin: .3em;
    padding: .3em;
}

#selection {
    border: 1px solid #ccc;
}

JavaScript

// First, get the <select> element. findElementsByName() returns a collection,
// we only want the first elements that's found (hence the [0]):
var choice = document.getElementsByName('choice')[0];

// Now, get a reference to the <p> where we'll show the result:
var selectionP = document.getElementById('selection');

// This Array will hold the labels. label[0] will be 'Text1', labels[1] 'Text2', etc.
var labels = [
    "Text1",
    "Text2",
    "Text3"
];

// Now attach a handler to the onchange event.
// This function will be executed if the <select>ion is changed:
choice.onchange = function() {
    var optionIndex = choice.selectedIndex; // The index of the selected option
    var text = labels[optionIndex]; // The label that corresponds to that index
    selectionP.innerHTML = text;
};