Since the development board you selected is the Seeeduino Cortex M0, you need to select Seeeduino Zero in arduino. There is nothing wrong with the development board you have chosen.
Because you have a Grove_-Motor_Driver_TB6612FNG library error. Have you updated or re-downloaded your library? I used seeeduino zero and downloaded the Grove-_Motor_Driver_TB6612FNG library, which was able to compile successfully