anime perfectly adapted the manga so far. but then the anime sets up the atmosphere of horror feels really really well so there's that
I think they're both equally good. You can watch the anime first then read all the manga starting from chapter 1
Personally I would say go to the manga. The anime has adapted the story pretty well, it does have a slightly different vibe to it. However if you plan to watch it with subs, netflix has the habit of making inaccurate translations and has censored some stuff in a few languages
Is the manga better than anime for summer hikaru died? Like which version catches better feel