These 3 parts are rusted as shown in pictures, what parts are they so I can get them replaced? Thanks!

 

First picture is the transmission tunnel W brace, you can source a used one from eBay or a local salvage yard, I strongly recommend taking your replacement one and respraying it with some kind of undercarriage coating, something that's flexible like Rustoleum 248656. That piece flexes quite a lot and the paint cracks, then moisture gets down below the paint and you end up with that mess like the one you have.

Second picture is your rear differential, no need to bother with it rust isn't going to hurt it. If the discoloration bothers you then get a can of flat black paint and some cardboard to catch overspray and repaint the thing, tape off the "gear" on each axle as well as the wheel speed sensor that's picking up that gear signal.

Third picture is where someone hacked off your exhaust just after the y-pipe and did a muffler delete, get a can of cold galvanizing spray and some cardboard to catch overspray and just paint over the top of it with the cold galv if it's really bothering you. Personally I'd just find someone local with a used OEM coupe exhaust and put the stock midpipe and muffler back on. Muffler deletes sound pretty terrible on the coupe imo but everyone has their own personal taste.