<script src="../tools/jquery/jquery-3.4.1.min.js"></script>
<button id="test1" value="value1">Test 1</button>
<button id="test2" value="value2">Test 2</button>
<button id="test3" value="value3">Test 3</button>
<button id="something" value="something">something</button>
<input type="text" id="display" value="">
<script>
$(document).ready(function() {
// this function will only work when one of the first 3 buttons is clicked
$('button[id^="test"]').click(function(){
$("#display").val($(this).val());
});
})
</script>