New character leveling

So with a lack of a subreddit to refer to, here I am asking questions. It’s been a while since I’ve played seriously and I’m looking to get going with my son and a friend of mine. We’ve all got our classes and what not selected, but I’m trying to figure out if it’s worth trying to do older content zones. I missed out on Pandaria so I’d like to see it, but will we outlevel the expansion before finishing content? Same with any of the zones that list a level lower than 60.