The path to becoming a Security Guard in New Hampshire is unlike a lot of the other US states:
The difference is that there is no government required security training in NH.
To become a Security Guard in most states, you need to take a government approved Security Guard licensing course, not in New Hampshire.
However, you'll need training for specialized NH security.
In New Hampshire, the government body that controls security licensing is the DEPARTMENT OF SAFETY DIVISION OF STATE POLICE.