Turn the printer off and and then on.

Run the "Selftest" in calibration settings.

If errors occur during selftest, please fix them before going further.

In Settings -> Temperature -> Fan speed set a value at 130 if you print lots of PETG and 255 if you print lots of PLA. For other materials select according to your most used filament.

Run PID calibration in calibration settings.

Choose a temperature that matches your most used printing temperature.