JSFiddle - React, Tailwind, and code Playground

HTML

<form id="the-form" action="some.php" method="get">
    <input id="the-input" type="text" name="var">
</form>

JavaScript

$(function () {

    $("#the-input").trigger("focus");

    $("#the-input").trigger(
        jQuery.Event('keypress', {
            keyCode: 65
    }));

    $("#the-input").trigger(
        jQuery.Event('keydown', {
            keyCode: 13
    }));

    $("#the-input").trigger(
        jQuery.Event('keypress', {
            which: 65
    }));

    $("#the-input").trigger(
        jQuery.Event('keydown', {
            which: 13
    }));
    
});