What does 1 Kings 1:5 mean?

Meanwhile, Adonijah, Haggith's son, started bragging, 'I'm going to be king.' He got himself a chariot and horses, and fifty men ran ahead of him wherever he went. 1 Kings 1:5 - Modern Text Bible

(Adonijah, one of David's sons, tries to claim the throne for himself. He acts like a king before being crowned, showing ambition and entitlement.)