Bird Hunting

Need help with my first hunting season

I want to go duck hunting this year but i have a few questions about what gear i should buy. When it comes to waders I'm not sure on what thickness to buy. I see alot of 3mm and 5mm but Im not sure which one is right for me. I live in Michigan so Im not sure which one I would need to keep me warm.

I am also curious to know if Im going to have trouble finding the right size wader for my body size. I am only 5'6 tall and weigh around 130 pounds and wear size 30x30 pants with 8 or 9 size shoes. I am worried that the waders i will try on will be too big for me.