How to Process textbox value to variable in JavaScript

Question

I want to be able to type something into a textbox and then get an alert saying what I typed. Easy Right? I tried using getElementbyId and made some variables to accomodate with this, but it turns out it gives undefined. This is the code:

    <input type="submit" name="button" style="position: absolute; top: 283.5px; left: 45%; width: 142px; height: 40px; background-color:lime; border-color:forestgreen; font-weight:700; font-family:'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande', 'Lucida Sans', Arial, sans-serif" value="CLICK ME"/>
    <div style="position: absolute; top: 283.5px; left: 23%; width: 142px; height: 40px; background-color:lime; border-color:forestgreen;">
        <input type="text" name="linksubmit" id="linksubmit" style="position: absolute; top: 10px; width:138px" />
    </div>
    <script>
        var linksubmit = document.getElementById("linksubmit").value 
        function Button() {
            alert(linksubmit)
        }
    </script>

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If any of you have a valid reason why this could not be working, it would be greatly appreciated.

Answer 1

const theThing = document.getElementById('testerooni');
showMe = () => { alert(theThing.value) };

<input id="testerooni" type="text">
<button onclick="showMe()">SHOW ME</button>