Oh boy where to begin, this would take a while

2004 has ILS tutoring doesn't it? It's got to be in one of the many instruction guides/manual/tutorials.

Best bet is to grab an instrument training flight book. MSFS is no different then real plane.

I personally like the Mooney and King Air for ILS approaches.

Why don't you zip on down to the Brandywine airport off Paoli Pike and ask for a intro flight. I would suggest you start with VFR and VOR approaches then work up to instruments. Unless of course you're already there.