It means meals and a place to sleep are included. "Bunk" means to sleep.

A bunk is a bed, so saying - you'll bunk there with your pals means that you can sleep there with your pals. The bunk house is like a dormitory with a number of beds, a sleeping room. "It's bread and board" means you will be fed, you will be given food to eat (bread) and you will be given a place to stay and a place to sleep (board). If you are a 'boarder' in someone's home, then you pay for 'room and board'. You pay to have a room in someone's house and you sleep there and are given food.

Thanks!

That type of school, where the children live and sleep, is commonly called a "boarding school." Such schools are sometimes sought by parents who don't like to spend time with their kids, or who are not good at parenting.