He told BBC Radio Cambridgeshire: "I've had the pleasure of playing at the junior levels and I want to push on to under-21 and senior level.
"But I have to be playing first-team football which is why I am here."
The Ghana-born full-back failed to secure a long-term deal at Stamford Bridge but managed eight appearances during a loan spell at Dagenham last season, scoring twice.
"Working with the likes of Frank Lampard, Michael Ballack and Deco at Chelsea you learn a lot," he said.
"You watch them train, you train with them and when you need help they're always there to help you and you're always picking up a few things from them.
"If someone wants my opinion about stuff, I'm very available to give it to them and if I think something is not right I'm also going to express my opinion."
Ofori-Twumasi, who prefers to be known as Nana, will have to fend off competition from fellow full-backs Scott Griffiths and Mark Little if he is to feature in boss Gary Johnson's first-team.