In the United States, each state is free to make its own laws about how the beaches are used. In some places the beaches are private and beaching your boat there could get you a trespassing charge. In others the beaches are public. Even there, though, there might be local regulations
against beaching a boat and sleeping on it overnight.
Bottom line, if you want to remain legal
, then every place you stop--not just every state, but each little town along the way--you will have to check the local laws. Or you could just beach it and hope for the best. There's a good chance that no one would even notice you, and if they did you would just be told to move along.
There is, however, the possibility that you might get fined or even arrested. Probably a very small possibility, but something to at least be aware of.