It's probably because i didn't have time for tutorials (The arrows were the closest thing i could get to making one). Basically you're supposed to gain a lot of speed (There are various methods for this. If you don't know any try to experiment) then jump and dash diagonally upwards (The reason the arrows are there) and then if you gathered enough speed you can get to the platform with the exit.
If i were to make updates to the game it would probably be some tutorial levels that explain this kind of thing