JSFiddle - React, Tailwind, and code Playground
HTML
<label for="">Enter Value</label>
<input type="text" id="product">
<select name="" id="platformid">
<option value="0">Assay Value </option>
<option value="1">STANDARDDEVIATION</option>
<option value="2">ACCEPTABLEMIN</option>
<option value="3">ACCEPTABLEMAX</option>
<option value="4">Date</option>
</select>
JavaScript
$("#product").on("change keyup paste", function(){
var valuefound ='';
$("#platformid option").each(function(i){ if($(this).text().substring(0, 2).toLowerCase() ==$("#product").val().substring(0, 2).toLowerCase() ){ valuefound = $(this).val(); } });
$('option:selected', 'select[name="platformid"]').removeAttr('selected'); $('#platformid option[value="' + valuefound + '"]').prop('selected', true); })