If you want a good history on Vaporwave in relation to aesthetic, the Aesthetic Wiki is a really good resource, here's the link to their page on it. I also think it's a really fun wiki to browse and I totally recommend it if you're new to the internet in general!
I'm not trying to discourage discussion by outsourcing an answer, just these links are probably the best explanation I can personally give, since they're a lot more thorough than I can be. I'm sure other people here can explain it well in their own words, so no worries.
I hope you have fun here!