Pus came out

Why I there pus coming ou from this bump on shaft on my penis

Probably because there's an infection.

Time to go to the doctor. It could just be a pimple but it could be something worse. Without actually looking at it (NO! Don't post pictures!) we can only guess.

Make an appointment and don't squeeze it, you're only allowing bacteria to go into an already infected area.

why i there pus coming ou from this bump on shaft on my penis

Since I can't examine it (please don't post a picture), and since I can't test the pus, I guess you need to go to the doctor.