You don’t have to worry that you will be behind everyone if you miss a meeting. Everyone does projects at their own pace. For example, in one meeting, we can have people doing Project 1, Project 3, Project 7, all at one go!
You are encouraged however, to keep up with your progress of doing projects. This is important as once you have not done projects for a long time, there is a chance that you will become rusty, and this is counter-productive towards your achievement of public speaking skills. The club does not require attendence, but you can only get from the club as much as you put into it.