Look for raw denim! The real stuff- it’ll feel thicker at first and will take breaking in. You’ll be paying 100+ most likely, but they’ll last you a lifetime. Brands are really dependent on the style/cut of jeans you’re looking for. Not up to date on brands anymore since I haven’t had to buy a new pair in over ten years. My favorite brand was/is Rogue Territory, but I’m not sure if they are available in the EU.
It kind of comes down to the overall craftsmanship of the jeans. I started paying more attention to the seams, stitching, and where things lined up on my body. I had good luck purchasing from smaller brands which appeared to value the ‘legacy’ of denim- not something I really think about, but I was happy they did.