Papua New Guinea is a Commonwealth realm with Elizabeth II as Queen of Papua New Guinea. The constitutional convention, which prepared the draft constitution, and Australia, the outgoing metropolitan power, had thought that Papua New Guinea would not remain a monarchy. The founders, however, considered that imperial honours had a cachet. The monarch is represented by the Governor-General of Papua New Guinea, currently Bob Dadae. Papua New Guinea, and Solomon Islands, are unusual among Commonwealth realms in that governors-general are elected by the legislature, rather than chosen by the executive branch.

The Prime Minister heads the cabinet, which consists of 31 members of Parliament from the ruling coalition, which make up the government. The current prime minister is James Marape. The unicameral National Parliament has 111 seats, of which 22 are occupied by the governors of the 22 provinces and the National Capital District. Candidates for members of parliament are voted upon when the prime minister asks the governor-general to call a national election, a maximum of five years after the previous national election.
https://en.wikipedia.org/wiki/Papua_New_Guinea