Is there a way to get games/computer programs to read from the my doents folder on my H drive instead of C?

if you have these games installed your H drive than all you need to do is find them on the h drive and make a shortcut to your games on H if you installed your games on the c drive you can copy and paste your program files from C to H but since it goes into your reg on that comp there no way you can unattach your ext hdd than lets say go to your friends house and plug into his comp and play your game thier since all the video codec was written to the original comp you installed the game on