how to fix this error Assets/Scripts/PlayerControler.cs(13,5): error CS1520: Class, struct, or interface method must have a return type

i dont know how to fix this error

This is really a question about C#, not Unity. If the problem isn’t readily apparent from the error message, then you should invest in learning C#. I suggest HackerRank for that purpose.

Anyway. In simplified terms, a C# method looks something like this:

ReturnType Name(ParameterType1 parameter1, ParameterType2 parameter2, ...)

The ReturnType is the kind of thing that the method returns when it exits. There is a special return type called “void” which means “this method doesn’t return anything”. You can have as many or few parameters as you like but each one must have a type and they all must be assigned.

If you didn’t write PlayerController.cs, then you should take this up with the person who did.