the doctor should find it smooth (not bumpy / lumpy) and it should feel like the size is appropriate to your age. A hard prostate is not a good thing, but it's not the only thing a doctor will consider. (From 12, our prostate glands grow pretty rapidly till middle or late teens, then very slowly until we die) A bumpy or large or hard-feeling prostate will cause the doctor to order a PSA test and maybe a biopsy. I
Because of the location and angles, you CAN'T really check your own prostate. Scaly? No, but the finger up the butt is not actually touching the prostate itself.
Prostate cancer is REALLY rare for men under 45 or 50. If you're under that, you can probably get a doctor to do a DRE, maybe order a PSA test after that. But if you're under 45, with no symptoms, it's likely that insurance will NOT pay for a lot of tests.