Yes, you can use a display with the system.
You need to hook the SPI pins to these: openmv/src/omv/boards/ARDUINO_NICLA_VISION/omv_boardconfig.h at master · openmv/openmv (github.com)
You can get the Nicla Pinout here: ABX00051-full-pinout.pdf (arduino.cc)
And the LCD shield pinout here: https://openmv.io/cdn/shop/files/lcd-pinout_2048x.png?v=1613516978
There’s 6 data pins and power/ground you have to hookup. Then you can use the SPI Disiplay module to send images to the screen.