im trying to do it for a league and i can't estimate how many laps it would take on a track in an hour

Use this command: /hours X (where X is how many hours you want the race to last for).

Yes,one option would be set specific time in hours - race is over when time is up and the leader crosses the finish line.

Other option - calculate. For example you want the race last about 1 hour long and you have for example a track/car combo with laptime 1min30. Convert the hour (3600s) and laptime (90s) in seconds and divide it like this:
3600/90=40
This means 40 laps of racing will be about 1 hour long.

thank you

In the lfs folders there is command.txt file with everything you need to know about commands

Quote from lucaf :

In the lfs folders there is command.txt file with everything you need to know about commands

stop spamming forum and race!

just keep increasing the lapcount by right-clicking: at 1000 laps it will change to 1 hour, 2 hours etc