Well... it would be for if you click a button then text or something comes up... that is easy.
But I really suggest you take a class on Flash or something, it is extremely hard to learn through the internet or with books. You should have at least a basic understanding of it before you take the free trial.
I learned completely of of youtube videos because I couldn't take the class that summer and because Newgrounds never worked. I suggest if your just going to use the trial then you wouldn't be able to make a game good enough for AG because you still have to learn actionscript first. But yes you can make a simple button that says text
Most game makers make games very quickly, so yes the trial would be fine. However, I take months on my games because I don't expect any profit and have lower motivation.