When most people search for "unlock all tracks," they are actually looking for a shortcut to access the mode (the 200 "double driver" tracks) or the Lagoon Black series (arguably the hardest tracks in racing game history).
The game has a built-in track editor and a variety of pre-made tracks, but some of them might be locked by default. To unlock all tracks, you can try the following: trackmania turbo unlock all tracks
Hold the Left Shift key and press: Up, Down, Left, Right, Up, Up, Down, Down. Environments to Master When most people search for "unlock all tracks,"