Ok fielding a few questions, so here goes.
Everyone who shows up for your team needs to bowl in one of the first two games of a match. EXCEPTION: If your opponent only has four or five players, you have the option to match them, but please make sure it’s a team decision and no one is being benched involuntarily.
For baker games (or tiebreakers) play five players. If you only have four, your opponent can choose to roll 4. If you have 6 and are in a best of two baker match, everyone has to be in at least one game.