The quarterback was the first passer picked this year, being chosen third overall by the Jacksonville Jaguars, while the Browns waited until the 22nd pick to draft Johnny Manziel.
The 22-year-old told the Ohio News-Herald: "I definitely thought there was more of a possibility I'd be here than Jacksonville, but that's not the way it turned out and I couldn't be happier to be where I am.
"[Manziel is] way more under the microscope. He's way more of a celebrity than me. He's got a lot of stuff to deal with that I don't have to."
Bortles faces competition from Chad Henne for the starting role at the Jaguars.