If you're hunting for a legal place to read 'Jujutsu Kaisen', the best starting points are the official publishers — they're the ones keeping the series alive and paying the creators.
MANGA Plus by Shueisha offers official English chapter releases for free on its website and app; it's great for catching up with recent serialized chapters and seeing the official translation quality. Viz Media (the English license holder for the collected volumes) also publishes chapters on the
Shonen Jump site and through the Shonen Jump app, which gives you access to the entire back catalog if you grab their low-cost subscription. I find the app handy for reading on the go and their translations are polished, plus they often include extras like designer notes or volume previews.
If you prefer owning volumes, digital storefronts like Kindle,
kobo, BookWalker, Google Play Books, and Apple Books sell official e-volumes of 'Jujutsu Kaisen', and physical copies are available from retailers such as Amazon, Barnes & Noble, or your local comic shop. Buying volumes or subscribing to official services is a direct way to support Gege Akutami and the whole team. Don't forget public library apps — many libraries offer manga through OverDrive/Libby or Hoopla, so you might borrow volumes for free depending on your local branch.
Beyond those, check regional publishers for translations in Spanish, French, Portuguese, etc., since licensed versions vary by country. Avoid scanlation sites — they rob creators and often have messy scans or dubious translations. Personally, I love rereading my favorite arcs in a printed volume; the art pops more and the translations feel tight, so I usually buy at least the volumes I want on my shelf.