Mini Control Board X3 is designed only as remote controller. Itself it can’t be programmed, only accepts commands from remote devices over Bluetooth (e.g. smartphone).
For any programmable applications, there comes RoboBoard X4, which has same remote control feature + run uploaded Arduino sketches.
You have mentioned Gripper Bot example in Totem Library. It is created to demonstrate how to connect to Mini Control Board X3 from ESP32 Dev Board (or any other, containing ESP32 processor).
Some documentation can be found here: https://docs.totemmaker.net/remote-control/arduino/
For this, use official ESP32 Arduino core version 1.0.6: Installing — Arduino-ESP32 2.0.2 documentation
Keep in mind, that Totem Library is currently outdated. Earlier it was used for X4 programming, but now it has it’s own implementation. So this library is expected to be updated in future to drop deprecated X4 implementation, support latest ESP32 versions, make it compatible with current X4 software, introduce objective API for X3 board.
Similar thing was also talked about here: VScode -> Platformio -> ESP32 -> Build failed : assembly debendencies?