If not, it may still be protected in your state by local laws. In general the requirements of a snake are minimal. They need shelter of some sort such as a hide box for them to feel safe in so as to keep stress to a minimum, a water bowl and a very secure enclosure. Aquariums with the plastic tops are generally not recommended because, depending on the species of snake, they will find a way out or push the top off. A terrarium with sliding glass doors that can be locked is best.
Snakes are carnivores only.
Many species of snakes are so called constrictors. They eat mainly small rodents and sometimes small birds. Feeder mice can be bought from a pet store in all sizes for feeding snakes. Other snakes eat mainly fish and other species eat frogs and toads. A few of the smaller species eat insects.