I'm curious about the effectiveness of hair loss treatments.

I have many questions about hair loss procedures. After watching related videos on YouTube, I learned that among hair loss treatments, hair transplantation has stricter requirements than I thought. I heard that it is not a procedure anyone can undergo simply because they want it, and eligibility depends on factors such as the severity of hair loss and the amount of hair on the back of the head. I also heard that there is a limit to the amount of hair that can be transplanted at once, so it is difficult to expect results as full as a wig. I would like to know more about hair transplantation in detail, such as who is actually eligible, how the surgical process works, and the recovery period and effectiveness.