What color is best for hiding gray hair?

Hello! I've been consistently maintaining my long hair. My hair is thin and weak, so I think a bob would make it look even less voluminous. As I get older, I'm getting gray hair. I've never dyed it before, but would natural brown be okay? Should I go to a salon for a full dye first, and then do partial dyeing myself with similar shades afterwards? Ugh... it's so stressful. Are there any hair dyes that are less damaging to the scalp and easy to use yourself? Are there any effective hair masks available after dyeing? Thank you in advance!