I’m new - i need advice

Hey everyone!

I'm a 20 year old girl from Belgium and i have one major issue

I'm starting to get grey hair.. mostly on the top-back of my head.

Now i'm wondering what to do about it.. i have a few options:
1) I could dye it permanently, but thats unhealthy for my hair i think and also you can't change the color back..

2) I could also just colour it with a special shampoo or something like those thin,gs from loreal and stuff.. so that it washes out after a while.. but with that technique i'm afraid that i won't have different colours anymore, do you know what i mean? Now i have different colours of brown, but when i color it with a shampoo i'm afraid it will be one colour of brown and i'm afraid that that will look unnaturally..

3) My third option is to try a product like gracian or re-nature.. but i wonder if those products help..

What doo you think?

Bye and thx