Pan on low heat or bowl for alfredo? It’s my first time making pasta and I’m really confused.

I’ve decided to try making Alfredo pasta with parmesan for the first time, and I’ve gone down a bit of a rabbit hole watching video and now I’m even more confused. I want to keep it authentic and i keep seeing two different approaches. Some mix everything together in a bowl after boiling the pasta and others are just doing it on low heat. These are just two different approaches, but I’m not sure which one i should follow. The main ingredients i have is a block of parmesan, unsalted butter and the pasta intself. submitted by /u/Exotic-Custard-8293