It depends where you live. There's no one company that's implented in all European countries. All countries have a shop similar to Amazon (often with fewer sponsored products and less drop shipping garbage). There are also a few specialized shops (for books, sports, electronics...). Since 2020 I only buy Amazon if they're significantly cheaper than other sellers. That's about 10% of my purchases.

In DE probably Otto.de is the closest you get (?).

In NL I remember Bol was quite good.

Yeah bol and coolblue are good in Holland

For clothes Zalando is a big one.

Beyond that it gets fragmented into companies serving only a few markets. Alza, Cool Blue, and Media Markt are some that come to my mind.

There's galaxus.com

Galaxus.eu, even.