Menu tree & tiny fonts

I’m a newish user fumbling my way through the program.

My usual issue with any new software is “Where is X located?” and that’s true here as well. Is there a published menu tree showing where all setup commands buried in there somewhere are located?

Another issue I have is some mail arrives with fonts so small I can’t possibly read it. Is there any way to force all messages to be the same size, or at least a minimum font size?