How many sessions do I need to see results from the hair loss treatment?

I have a few questions regarding hair loss treatments, so I am writing to ask.

I have a troubled scalp. Perhaps because it is oily, I often get breakouts, and when that happens, my scalp becomes red and sensitive. I am wondering if I should wait for my scalp condition to calm down before getting hair loss treatment, or if it is possible to receive the procedure even while I have these issues.

I would also like to know how many sessions are typically required to see results from hair loss treatment. It seems like I need to get treatments periodically to see effects, so what is the treatment cycle and recommended number of sessions?

Also, please let me know if there are any special precautions to take immediately after the hair loss procedure.