An addEventListener with keydown results in an empty string upon the first key in a textarea

I have a textarea tag that takes in values to use for something else. When I press on a key, the value of it is an empty string. However, the keys pressed after the first key show up just fine. For instance, if I type, “hello” the value would be, “ello”. I want it so the value of the first key would show up.

Rendering HTML inside textarea

I need to be able to render some HTML tags inside a textarea (namely <strong>, <i>, <u>, <a>) but textareas only interpret their content as text. Is there an easy way of doing it without relying on external libraries/plugins (I’m using jQuery)?
If not, do you know of any jQuery plugin I could use to do this?