Not declared in scope?

As you can see here there are lot of errors saying " not declared in scope". How do i fix this?

A change that was made in 2019 for C++ was to remove the shim that put using namespace frc; in the code for you. Do you have using namespace frc; in your source file? If not, you can add that or prefix things like Joystick and DifferentialDrive with frc::, e.g. frc::Joystick.

While I think that’s the problem, it’s helpful (almost necessary) to include (preferably a link to) your code when trying to help with compiler errors.

Sorry about that here’s my code. I added it and its still doing the same thing

How did you create your project? It doesn’t look like you used one of the WPILIb templates in the project creator.