Playing Rainbow Six Siege on other Acc, is that possible?

I always play Rainbow on my PC. I bought Rainbow on Steam. My friend who plays Rainbow on PS4 wants to give me his acc now because I'm banned to my main for 2 weeks. Now I just wanted to know how or if it is even possible that I now play on his Acc.

Hopefully you can help me.

You can't play on the PC with a PS4 account. Rainbow Six: Siege accounts are not cross-platform

No, you can't.