its a politician who holds public office in a national or regional government, making and implementing decisions on policies in conjunction with the other ministers
PMQs info:
officially known as Questions to Prime Ministers
is a constitutional convention currently held as a single session every Wednesday at noon when Commons is sitting during which PM spends 30 minutes answering questions from MPs
more info on PMQs:
the leader of opposition (the party that came second in election) usually asks 6 questions at PMQs, either as whole or in 2 separate groups of 3
this is prime example of how Commonsscrutinises the work of the PM and government