Flood said: "The manager called me in and said 'We like your drive, we like your enthusiasm and we like your ability so it's up to you to kick on from there.'
"I think I can learn from Gordon Strachan, Neil Lennon and Garry Pendrey and the lads here as well. I think I can learn from every player at the club because the standard of player here is frightening.
"I just think I need to work hard in training and catch the manager's eye, and then it's up to the manager if I'm good enough to get into the team."
The former Manchester City player, who made his Premiership debut at the age of 19, can also start to think about Champions League appearances but he is keen to focus on short-term goals as he begins his Celtic career.
"That's a long way away," he said. "I just think I need to establish myself in the team first and work hard in training, and hopefully I can play in the Champions League next season."
"It's in the back of my mind but I just want to catch the manager's eye and get into the team before the end of the season."
All the best Willo
Yours in Celtic
Clydebuilt