You should read and internalize the Richard Riley post
very carefully.

If you try and fail on a class III medical, you are totally
screwed virtually forever. Failure on class III eliminates
you from the sport category unless you can somehow
qualify for the class III later.

If you never fail and you have no medical problems,
you can fly sport without any further checking.

I'm with those that say you should find a completed
701 and get started!! Bill Hale