Currently on-loan at Barca from Manchester United, the England attacker is playing his way to a permanent deal with the Blaugrana.
"Signing for Barça has given me new energy, a new style, and a new country to explore," Rashford told ITV Football.
"I feel like the team fits me perfectly and that I can help them a lot. It's a big step, and I'm optimistic about the future.
"I think England will also see the best version of me after arriving at Barça. It's still early, but when I reach my full potential, I'll be the best version of myself."
In just 10 matches, he's scored three goals and provided five assists , but he believes his best is yet to come: "I'm very happy to be Barça's top scorer and assist provider right now, but I know I can still do better."