i was wondering something tho. would i be allowed to mod story mode? i do i have to be completely offline? like how exactly dose it work?
You don't have to be completely offline (as in: disconnected from the Internet; in fact, the game periodically uses your connection to validate you). So, as long as you restrict yourself to Single Player only, you're good.
Yup, Single Player won't get you banned. But be careful when you have modified RPF's because R* scans for them when going online and this will most likely get you banned. Also, normally ScriptHookV closes the game when trying to go online but in case you bypassed that or the process failed, the chance of getting banned is VERY high. As soon as the game detects that you hooked the script engine (for rage::scrThread etc.), you'll be flagged for investigation by a R* employee. There's another way that doesn't require hooking the script engine, which would allow you to play with high-level script mods in GTA Online almost undetected but I'm not going to share the method here for obvious reasons.