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How do u get the roms/games?

Solution 1 (and the only quasi-legal way): Roll your own. This means owning the game in question, and dumping the contents of its ROM into a file by various methods.

Solution 2: Download the ROMs from an emulator site. This is obviously not legal if you don't own the game in question, and many ROM sites rival porn sites for malware. You'll have to Google for the sites, as discussing specific ways to get copyrighted material is frowned upon in this forum.
 
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