First off, install/upgrade your library with the Library Manager
You have an HX8347 controller. You must enable support by editing MCUFRIEND_kbv.cpp and removing the two slashes in front of #define SUPPORT_8347D
There are instructions in the how_to file.
There are instructions in the diagnose_TFT_controller sketch
If your original library has come from Elegoo and not from the Library Manager, it is wise to delete the whole MCUFRIEND_kbv directory and start again (with the Library Manager)
David.