There is a general election on 12 December and if you are 18 years old then you are entitled to vote. But you can only actually vote if you are registered to vote.
You have until midnight on Tuesday 26 November to register to vote. It takes just a few minutes to register.
Without wanting to be sanctimonious about this, people have suffered and died to give you the right to vote, and to help choose your MP and less directly the government of the UK.
There are different deadlines and registration processes for postal and proxy voting, and the deadlines differ between Great Britain and Northern Ireland – check here.