Making a custom ChatBox


I would like to know if someone could show me how to make a chatbox, which would in fact, replace the normal one.
So basically I am requesting a tutorial, or more like a base.
I am simply asking for a very simple base from which I can develop.
Plus adding the feature to the box, when you press the key “Y” the custom chat box displays.

Hope someone can provide a base.

Thank you.

Nobody has something? I only need a simple base to develop from.
Thank you.

(User was banned for this post ("Bumpity bump" - mahalis))