https://github.com/lvgl/lvgl_esp32_drivers/tree/develop/lvgl_7.11.0_idf_5.0 is a good reference to start with, although it is a little bit oudated and does not work on newer devices like ESP32C3, the functions and struct definitions are pretty much standard and can be copy-pasted to official example...

ILI9341 is widely used across ESP-IDF examples, e.g., https://github.com/espressif/esp-idf/tree/master/examples/peripherals/spi_master/lcd and https://github.com/espressif/esp-idf/tree/master/examples/peripherals/lcd/spi_lcd_touch. You may run these to check whether it works. After that, the process...