I’m stumped!

My client wants to select a start date for up to 15 marathons per year and automatically have each one populate 182 days of training activities at 6 unique levels of skill.

Beginner Half
Beginner Full
Intermediate Half
Intermediate Full
Advanced Half
Advanced Full

Each unique level has the same activities associated with it regardless of the marathon or start date.

He wants a user to be able to choose a race and a skill level and have those specific 182 days only show up for that user.

I’m looking for the best way to achieve this. I was hoping for a way to choose those 2 variables and have a calendar filter out everything but their choices but I am about to die.