So with regular mods if you want to play online you just uninstall ASI Loader. So is there any way for me to disable ragepluginhook to play online when i want or do i have to get a seperate copy of gta v just for LSPDFR?

Simply launching the game the regular way, rather than through RPH, should in theory be fine as RPH won't get loaded that way. This is no guarantee though, as we still don't know the extent to which Rockstar scans the game folder when going Online.

RAGEPluginHook doesn't start automatically, it only starts when you launch GTA V via RAGEPluginHook.exe.

All I do is just use the default launcher when I'm trying to play GTA Online, and then use RAGEPluginHook.exe if I'm trying to use LSPDFR.