The former Arsenal captain feels joining the Blaugrana was crucial in his development, while he feels Spain is not the favorite to win the Confederations Cup.
Since joining the Catalans in 2011, the midfielder has become more of a key player for Spain's national team, having been on the peripherals while Arsenal captain.
On the back of a 2-1 over Uruguay in the opening match of Spain's Confederations Cup campaign, Fabregas stressed how crucial the transfer back to the club of his youth was to develop as a player and become one of the world's greatest.
He told FIFA.com: "I think moving to Barcelona was a very important step for me, because of the system and also because you’re playing with the best, which means you automatically have to move up a level to match the standards they set.
"You learn something in every training session and you have to give your very best."
Fabregas played an important part in the team's victory over Group B opponent Uruguay on Sunday and the 26-year-old is pleased with Spains start to the only major international tournament that the country has yet to win.
"We played well and it was the complete performance," he stated. "The important thing is the three points and the way we controlled the whole game, not the way I played. A start like this always gives you confidence for what lies ahead.
"I’ve been playing for Spain for eight years, which is a long time, and I can remember some games we’ve played and some individual performances where we’ve been at a similar level. The important thing, though, is that we played well and I felt comfortable. That’s what counts to my mind."
Despite dismissing any champions elect tag, the Barca attacking midfielder is adamant that a focus on controlling the flow of the clashes will see the team go far in the Confederations Cup.
"I wouldn’t say we’re the favorites," he stated. "We’re just trying to play our game and our tournament.
"We can win it, just as long as we do what we know best, which is to keep possession and control the pace of the game. When we do that, we’re very difficult to beat, as we’ve shown."
Spain faces Tahiti on Thursday in Brazil.