Yes, that is something you'll learn about when pursuing this. It is a must because you need it to debug your emulator.
I'm afraid that a NES emulator is very far from your level right now. It would be many years before you can attempt such a thing. Plus looking at an emulator when you are not proficient enough in programming may overwhelm you... on top of making it seem impossible.
What I'd suggest is that you set your goal of programming to something more realistic for your level... something like making a game, a Pong game, or a text adventure game, and forget about emulation until you are able to write at least a Mario clone game.
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cChip interpreter WIP - current status: Release Candidate
LRx Filter RC - current performance rating: 9/10