How do I get to play nes games on dreamcast with the emulator

What do I do to burn the emulator and the roms so I can play them on my dreamcast. I was told that you can do that. I don't know what to do, I have no idea abotu anything, and I have looked through the post for this. I have the utopia bootdisc burned but I don't know what else to do, and I don't know how to get clone dc games.