I’m not sure what the part is called but the flange that connects the exhaust to the engine lets a lot of air escape. There seems to be some kind of metal ring/donut in between the flange that spins simply by touching it. I already tried tightening the nuts on the flange but it didn’t solve anything. What’s the part called and how do you fix/replace it? My car sounds horrible and performs poorly because of it.

Ive attached pictures of what I’m talking about.
Thanks for any help in advance

 

Looks like maybe, "exhaust donut" (lots of deeply technical terms around cars sometimes, eh? )

I would suggest while you have that apart, replace the nuts; get brass ones instead of steel. Don't overtighten them. Use PLENTY of penetrating oil before trying to take it apart, lest you break off the studs.

 

So I tried finding a replacement exhaust donut/gasket to replace the one that keeps spinning on my car but no luck.
I have an exhaust repair putty that is used to seal cracks on the exhaust (quiksteel high temp metal repair)
Can I just seal the whole gasket/donut to prevent the air from escaping? I want to put a v8 in this car eventually so I don’t care much for the v6 headers.

I’d take it to a muffler shop for a proper fix but can’t really afford that now and this is currently my daily driver.
I do plan to buy a cheap pick up truck with tax refund money so that I don’t have to drive this poor 32 year old car everyday.

 

Why can't you find one? There's A WHOLE BUNCH of choices on rockauto.com for example. Being as how some are FelPro, you ought to be able to pick it up at your local corner parts store.

Calls itself "pipe flange gasket" over there. Cryptic I know, but...