Is this for real???? If so awesome!!!Does/did Wii game in question have Classic Controller Support? Y/N
If Y: You can use the Wii U GamePad to control.
If N: You cannot use the Wii U GamePad to control. You must use Wii Remote.
Your Wii game-of-interest that does not have Classic Controller support has not been patched to transfer Wii Remote controls to the GamePad.
Edit: nvm read that wrong