A/C clutch on 2000 Plymouth Voyager


I have a 2000 Plymouth Voyager, the a/c was not working well so I purchased a can of freon and a guage and added some freon to it (it was low). However, now the belt will squeal and we can smell it burning sometimes - especially when the a/c is off. Before this whole thing started the old belt did break and I replaced it. It has now broken again. Since the belt squealed often even with the a/c off, I am thinking it is the a/c clutch, but I don’t want to do replace that without making sure the a/c itself is good. I will buy a belt, but then what other tests can I do at home to see if the a/c unit itself is working right before I shell out the money to buy a a/c clutch? Also, how tough is it to replace an a/c clutch?