Serial.print shows nothing, Serial.available is never > 0. Normal ?

I see lots of examples in the Arduino IDE where it should work, but not for me. Notably, I connected some camera to the groove/uart port, programmed them, Serial or various attempts of SerialPort are all unavailable.

I have a GRAY (m5stack ESP32), wondering if it has a hardware issue or if it is something with programming. I have spent many dozens of hours on this, if you have a view it is very welcome.