Best wavy and curly hair shampoo/conditioner and routine?

When I was younger I used to have stick straight hair. As I'm getting older it's getting a lot more thick and the bottom layer is getting really wavy and it looks great when I actually don't do much to it. The top layer is just weird, the ends flip in and out and its defiantly not as wavy as the bottom. I'd like a shampoo and conditioner that I can use a certain routine with that helps bring out the waves/curls but also helps with layer blending and that doesn't make your hair frizzy. I also have a defuser if I need that for the routine. I don't want to spend a ton of money either. Thanks!