I'll try and keep this short...
Its an F1 Management game. You are responsible for signing and training your driver, setting up the car for each race, deciding on a strategy (fuel and tyres) and telling the driver how to handle qualifying, and a few other things. On top of this you can improve your team, upgrade your car, run test sessions, etc if you have the money.
Races run twice a week (Tues and Fri) and you have to qualify and submit your setup 90mins before. During the race you have no control over what happens, just your predetermined strategy. You can follow the race "live" with a lap updating every 2 mins, or leave it and check the results whenever is convenient.
When you join, you join in a rookie league, with up to 40 drivers. Finish in the top 4 and you get promoted. It's quite addictive, and the game engine is complex, so there's lots to think about, and you end up analysing all the data you get to perfect your next strategy. If you don't like looking at lap times and fuel consumption data, it's probably not so interesting, but I'm enjoying it, having only done 2 races. If you join now you'll get 3 or 4 races to get used to it before the next season.
Everyone on here was really helpful when I first joined, and the GPRO group has loads of helpful stuff. If you don't like it you've not lost anything!