Wen i was little i had a testicle remove ...because they say it was up it my stomack..so can i have bby?

Depends: Most of the time cryptorchidism or undescended testis is only one. It is a risk for cancer later. It has been removed. If you still have one normal and functioning testis, then you should be fine and be able to be a father.

If 1 down likely yes: Fertility should be ok, assuming the other testis is fully descended ; normal, or even larger than normal.