The Brazilian midfielder has struggled with the pace of the Premier League since joining United from Real Madrid in 2022 but he is determined to remain at Old Trafford and fight for his place in Ruben Amorim's team.
Casemiro told the Spanish newspaper Diario AS: "I have to keep doing what I'm doing, with a lot of respect, and good behaviour.
"Of course, I'd like to play more. I don't know any player who doesn't want to play. And I want to help the club at this time. I face things with respect for my teammates and the staff, and above all, respect for United.
"I have a year and a half left on my contract, and I'd like to see it out here in Manchester. I'm comfortable here, and my family is too. They've adapted, we speak English. I'm very grateful to the fans and the club. I'm happy at the club. Happy on the bench? Of course not, that's something else."
Pundits have suggested that Casemiro is past his best as he struggled at United but he insists that he has a "lot left to give" in his career.
The five-time Champions League winner said: "I'm young, and I've got a lot left to give.
"I'm about to turn 33. Nowadays that's like being 28 before - with nutrition, physical preparation, all that extending a player's career if you look after yourself. That's why Cristiano [Ronaldo] is still scoring 50 goals a season, at 40 years old."