California and Gun Control. My thoughts

If a state like say California unanimously decided (including citizen vote) to get rid of guns and or get really strict gun laws and even Congress passes it, could they?

If all Californians unanimously agreed to get rid of guns, why would they need to vote on it? Why wouldn't they all just throw out their guns?

I think what you mean to say is, if a large majority of Californians voted for that, could they do it?

Well…no. The right to bear arms is still a right no matter how many Californians dislike it. No number of voters in a single state can vote to abolish your Constitutional Second Amendment right.