Default (Q)New to devoloping, trying to alter an already built rom. Any guidance appreciated

I just have a couple questions, I've been adjusting theme zips by changing around files in the zip then flashing.

I wanted to alter a rom I have by changing the apks that are in the system/app , data/app, and framework folders. Usually I'm able to view apks as zips, but I'm the rom zip file, I cannot. I can't seem to write in the zip file at all...

And I can't change is permissions cuz when I go into the root section in my xplore file manager, anytime I view the sd or extsd Cards, I don't get the same options.

Any guidance is appreciated

You've Just Been Tapatold ♧♢dbombROMv3beta♤♡
☆FlappyBird☆Score ☆ 85 ☆
₩ňťř Χ ǜmįņğ