If my peewee team has 15 players on it's roster regularly and a few are sick and one is suspended, can I bring in as many affiliates as I want or do I have to leave out one for the suspended player? And for future reference am I limited to my roster size or can I bring up players to the maximum of 19 players?
You can affiliate up to 17 skaters and 2 goalies (as long as they are approved affiliates on the HCR) and it doesn't matter what your original roster size is or if you have suspensions.
Novice is different. Refer to Hockey Alberta Regulations for Affiliation for complete details.
What is the minimum number of players you need for a team to play?
According to Hockey Canada's Referee Casebook, in order to play a game, a team must have 6 eligible players (not necessarily a goaltender) to start the game.