Welcome to BVEStation.
Hmm, maybe I can take a crack at it. Since the (7) is the most easiest, I will try my best on it.
Oh, what about the (4)?
It is currently in development. There is a video here: https://www.youtube.com/watch?v=xLtdYPshgyo. You can, of course, develop a route on your own even if it's already in development. Just know that route developing is a very serious project.
That is not the 4 line that is the 6 line. There is a reason why they start on the wrong side of 125, go local, & terminate at Brooklyn Bridge. Don't get confused by the announcements.