How do i get my hair thicker and healthier

I have noticed more of my hair has been falling out and thinning. I have already made a dermatologist appointment the thing is i am quite young and dont know if they will just give me diet advice or actually give me something like minoxidil finasteride or things of that sort , please help me
When you say you're quite young, I'm assuming you mean late adolescence. If you're in late adolescence and you're losing hair, there may be more factors at play that can only be assessed by your medical providers. Before making plans, speak with them first to assess if there's something more significant needing to be addressed. They would be the ones able to do so.

After this, if they do say there's nothing abnormal, I've personally had good experiences with shampoos that use the word "clarifying". Those products are designed to address scalp oil which can make hair that's already thin appear even thinner. In addition, it's important to wash hair thoroughly, but infrequently. In order to maximize hair looking clean for multiple days between washes, I've had great success with Dede conditioner (linked below).

https://us.davines.com/products/dede-conditioner?variant=45483366678707