Thanks for your query.
It Is called Phimosis
That Is Inability to retract the skin of penis.
It Is a simple condition and do not worry about It.
Kindly visit a general surgeon
, you might have to undergo a minor surgical procedure called circumcision
It Includes removal of the foreskin surrounding glans penis
Hope I have answered your query.
I will be available for your follow up queries If any.
Wishing you good health.