Setting up Super Mario 64 on Wii Virtual Console in most circumstances requires softmodding a Wii to run homebrew, since
- the game can no longer be obtained through official means, and
- the version used for practice and typically for runs can only officially run on Wiis set to its own region, namely North America (NTSC-U).
This procedure splits into 3 parts, with guides linked for each. You will need an original-edition Wii (one with GameCube controller ports) to play SM64 on Wii VC.