Loading (scrollable) External Text in Empty MC?

I think this is either extremely easy and I just can’t figure it out or is very strange cause I can’t find any help with it on my own so here goes. All I need is to load external text (no problem) but I need it to load in an empty MC which will unload when another button is pressed to allow an external jpg to load (again no problem for loading the pic) just cant get the text to load in the empty mc. Also I need the external text to be scrollable which is another can of worms I know.
Thanks so much 4 your help!