Ronaldo played only 30 minutes of the win over Livorno.
The former Real Madrid hero said: “It went really well. I still have to learn from this group, but this is already a start which I like.
“I thank my team-mates because it’s not easy arriving and playing straight away. There’s still a lot of work to be done, but I felt well both with another attacker and on my own.”
He added: “The goals will arrive, and I’m very happy to be here once again.”