How many hair loss treatments are usually recommended?

I used to be worried because I had too much hair, but now that I am in my late 40s, I have noticed a significant amount of hair loss, and my receding hairline and the crown of my head look sparse. After much consideration, I am planning to get hair loss treatment.

I have noticed that there are various types of hair loss treatments offered at dermatology clinics and specialized clinics, such as exosome therapy and injections. I am curious about the typical treatment cycle. Also, I would like to know approximately how many sessions are recommended to see definite effects, such as thickening hair or hair regrowth.

I have a lot of concerns since I haven't purchased a regular pass yet. If anyone has any firsthand reviews or advice from actually receiving treatments, please be sure to share them in the comments.