New to the ps3 cfw scene, looking for tips

[AlmondMilk12]

Hi guys, I just got a backwards compatible cechc02 model and put evilnat 4.90 on it and just have a few questions

Is it better to mount isos or install pkgs to play games?

Am I able to play online on games that I dont legally own through disc or psn store?

Do I need to get into the habit of doing anything if I want to stay signed in to psn?

Any other tips and advice would be really cool too.
Thanks