GTA 5 ??

I bought gta5 from cdkeys and i had to download the game from the rockstar website, say if i get banned, will it ban my steam aswel even though it wasn't bought on steam and also will i have to buy the game again how would it work ?

Hello! Regarding to your post, If you have brought a game from a different website and you are currently, or previously hacked in it on steam. Then you will not only get a STEAMID ban but also your rockstargames account banned. :). It does not matter if you brought the game or downloaded it from a different website for example Battlefield 1 and you hack in it, your steam account is also going to get a ban.
To summarise everything, not only your steam account is going to recieve a ban but also your rockstar account. :)
Also rockstar will not give technical details on their system. First bans are 10-14 days, second ban is 30 days, third is permanent, as I can tell from experience but might be wrong. Anyway have fun!