Part of the biopsy procedure is to do numbing shots prior to taking the actual biopsies. The initial numbing shots are the most uncomfortable part of the procedure. I had quite a few cores taken so asked for an additional numbing shot when I could feel core shots - This numbing shot didn't hurt much at all.
Please note - I have always been horrible with shots, and I went through the biopsy just fine. Mayo-Rochester had a television in the room. I had them put it on HGTV and I talked to one of the nurses throughout the entire procedure - Really helped for me.
Based on my experience, I would not be too worried about the biopsy procedure, it is quick, relatively painless, and provides a lot of data for making your final treatment decision. I agree with some of the other comments - I would not make any final decisions on the MRI scan. This is an excellent tool, but it has limitations. I believe it is common practice to not only biopsy the lesions, but also take random biopsy samples from the peripheral regions of the prostate. In my case, Gleason 4/3 cancer was found away from the MRI detected lesion. I ended up going with a radical prostatectomy on November 3, 2022.
Good luck with your biopsy, and if needed, your treatment decision.

Jim