You can select a default zone from the list and even set the default zone. Out of the box, the default zone is FedoraWorkstation, which rejects unsolicited incoming packets from ports 1 to 1024 ...
Forget the bare minimum: here's how much RAM you actually need to get the best performance out of your Linux system today.
If I asked you which Excel tab you use most, there's a good chance the View tab wouldn't even cross your mind. The Insert, Formulas, and Data tabs usually get all the attention, and for good reason.