Ask the Declaration → Your rights, by who you are
The Second Amendment is one sentence with two clauses, and nearly every debate about firearms turns on how they relate. Here is the constitutional layer.
Descriptive, not legal advice · the founding documents' own words
A well regulated militia being necessary to the security of a free state, the right of the people to keep and bear arms shall not be infringed.
Protection against unreasonable searches and seizures, which bears on how firearms may be searched for or confiscated.
Due process, the vehicle through which the Second Amendment applies to the states, not only the federal government.