Myles Garrett tells TMZ Sports it "feels pretty nice" to be officially back in the NFL after his indefinite suspension ... and says he got better during his time away from the game.
As we previously reported ... the Cleveland Browns superstar was reinstated into the league on Wednesday after meeting with commish Roger Goodell and other NFL execs.
Garrett was punished 6 games for swinging a helmet at Pittsburgh Steelers quarterback Mason Rudolph back in November ... and had to seek counseling before making a return.
The 24-year-old spent a lot of time in the gym during his suspension .