If the foreskin can be opened after erection, there is no need to surgically remove the foreskin. Only those who can't open the foreskin after erection need surgery to remove the foreskin.

Now that it can be opened, open it to expose the glans penis. I'm not used to it at first, and I feel a little flustered and uncomfortable when I walk. In a few months, you will get used to it. Why do you have to take a knife? But yours may have turned back after it was opened. It doesn't matter. Pay attention to hygiene at ordinary times. It's good to always open the foreskin and wash the scales. It's best to wash it once a day before going to bed, and everything will be OK.