I'm really worried about hair loss.

Hello, let's talk about hair loss concerns through this event. As time goes by, I really feel my hair getting thinner. It feels like the thinning starts from the crown rather than the forehead. So, I'm curious whether switching to a different shampoo, even just for prevention, would be effective. Also, it seems like my hair loss is progressing, and I want to know how much hair can grow back if I take medication. I didn't realize how much hair loss affected me when I was younger, but now I definitely feel it as stress.