Javascript search words and color


I have an edit page popup that I have a HTML component that content a long text. I would like to have either a JS or any other tricks that can search specific words and highlight them.

So my goal is to highlight specific words in a color.

I have tried to embed some html tags like for testing purposes only and it doesn’t work. So I imagine the solution is a Javascript for if I can have some help and code it will be great.

This is very an important step for my APP.

If somebody can help today, so I will be able to work this weekend on it.

Thanks in advance