[Q] How to backup google apps before flashing? topic

Hi guys, I'm a noob that's never flashed before so please excuse me if this is a dumb question. I've been searching a lot for the answer to this but I couldn't find it. If I want to backup my google apps (maps, gmail, etc) before I flash my ROM, how can I do so. I would rather do that than download them from an online source as I don't know the legality of downloading them.

Also, how can I backup my stock ROM in case something goes wrong? I am able to reboot the phone into the bootloader screen.