I play Karlson but i downloaded a mod i accidently click instant win so the timer is like 2 seconds win or something

Unfortunately the process is different from game to game. The best way is to see if the game itself has a way to delete progress. If not, you can re-download the game, and progress should reset. Alternatively you can contact the developer for advice.

Unless you mean you want to delete the mod without affecting the game? In that case you would have to contact the developer of the mod, unless they have instructions of how to do that already.