First off we are not here to code for you, that's your job to do the work. We are here just to provide some help with problems. First off try to make a box using just normal text and fonts. Then add the bitmap font. Using a view for scrolling the text will probably (for you since you say you have no idea how to even start this) will prove to be more complicated than just moving the position of the text. Then the next part is to display the text. What about text wrapping? Your need to use a prexisting library for text formatting or write code yourself to wrap text to the next line when you run out of width in the chat box. Just some things to think about.
Once you get a basic chat box working then you can think about bitmap fonts. Your probably want to write a wrapper for taking a string and then displaying it using a bitmap font. Once you got that working combine it into your chat box.
And, I am at work at the moment and so I'm just writing some things that I thought of off the top of my head. There is still more to it than what I wrote, but you get the idea. Try to write something, then post your code so we can see where you are and then we can maybe give some more detailed help.