What laws to Native Americans have to follow?

Reservations are 'sovereign nations' with their own laws, codes, etc. but do work in cooperation with federal, state, county and other governments. Tribes, as sovereign governments, make their own laws as any other government entity can and does. Whatever laws the tribes p are the ones that have to be followed. Those laws may or may not be the same as laws off of the reservation. Tribes and reservations sometimes fall under state jurisdiction but in most cases do not. However, it all depends on the particular tribe and the particular state and what they have worked out between themselves. While reservations are part of states, they are, at the same time, separate from them. Smoking, fireworks, etc. fall under tribal jurisdiction when on reservations so it would depend on a tribe's laws on how smoking and fireworks are regulated.