First, make an account.
Second, select a challenge from the list.
Third, submit your score.
Fourth, be persistent and beat your previous score.
This site is here to give you fitness challenges to accomplish.
Pick a challenge and track how long it takes to complete.
Submit your score on the challenge's page to keep track of your performance and to see how you stack up against others.
Do your workouts and log your scores. That's pretty much it.
And for now, all of this will be free. So send to your competitive friends stuck in their homes.
If you want to go above and beyond, feel free to volunteer any expertise: design, usability, engineering, workouts, wherever you see a weakness.