JSFiddle - React, Tailwind, and code Playground

HTML

<form id="frm">
    <input name="ip" type="text" id="it" style="display:none;"></input>
    <textarea id='ta'></textarea>
    <input type="submit" id="btn">submit</button>
</form>

JavaScript

document.getElementById("ta").addEventListener("keyup", function(e){
    document.getElementById("it").value = document.getElementById("it").value + e.key;
});