Legions
republic
Many forms of government fall within these parameters.
Yes. A republic is a form of government in which the citizens choose their leaders and the people (or at least a part of its people) have an impact on its government.
The answer is autocratic.
A Roman republic
Democracy or a Mawcracy.
Any form of government that allows people to elect an executive leader is generally termed a "democratic" government. With that said, it means that the executive leader has the power to enforce laws. Generally speaking in such a government the legislative branch of the government normally allows for the election of legislators.
If you meant 'what form' - it's a democratic government.
We need a name of a leader.
they can volunteer & serve in a smaller form of government
That's easy! - most British Citizens are eligible to vote in Parliamentary elections, once they are 18. The Political Party that wins the most seats in Parliament will form a Government. The leader of the largest Parliamentary Party (and therefore the leader of the governing Party) becomes PM and head of the Government.
There are many different forms of government, including monarchies, aristocracies and meritocracies. The US government is a democracy, in which all citizens can vote for their leader.