What is the connection between Stands and Ripple Energy? I don't understand how Stands are connected to the Ripple Energy, which is from breathing. The third part does not seem that linked to the first two parts of JoJo.
I’m a third of the way through Part 3, and as far as I can tell, there’s minimal, if any at all, link between Stand and Hamon (Ripple) abilities. Initially, I thought the Stand was an extension of Hamon, since there’s a remark about Jotaro’s ability to fight while unable to breathe in his initial fight with Avdol, which other people on the internet have also noticed, but this doesn’t amount to much.

Discussions I found in a web search attest to this as well:


This Reddit thread and this Quora post discuss the relationship between Stand and Ripple. Posters cite Part 7, in which Hamon is indicated to be a stepping stone to Stand. (I haven’t gotten to Part 7, so I can’t judge for myself on the details.) However, this is seen as a retcon, and for the most part, people seem inclined to say that there’s not much relationship.
The fan wiki article on Stand and this Reddit thread, among other sources, note that Hamon was more or less discarded after Part 2.