I would like to buy a new laptop. It would be important to me that it lasts a long time (not just 2/3 years). It should have at least 8GB RAM, have to endure a lot (like to gamble for a few hours) and not be too expensive. Does anyone have a recommendation for me?
This is not possible with a laptop. You can be happy if he creates 3 years of current games. It will (at least if you invest a LOT of money maybe 5 years. But then probably no longer maximum settings at the games. So either you save a long time, buy a suitable gaming pc or are content to buy a new laptop in 2 years to have to.
A laptop is generally useless for gaming, because you are looking for the wrong device. In addition, the necessary hardware for games changes in 3 years, even if your laptop would last 10 years, it could play everything smoothly for a maximum of 3 years
Business notebooks usually have a long lifespan, but these notebooks do not have their own graphics card, which makes them largely unsuitable for gaming.
Typical business series during:
Fujitsu = Lifebook
HP = Probook / EliteBook
Lenovo = Thinkpad
I'd look for an EliteBook with AMD Ryzen.
My recommendation: either or not - don't look for the egg-laying wool milk sow.
If you choose "lifetime", I can recommend Lenovo Thinkpads. There were some with a dedicated graphics card, they were new but quite expensive.
If you choose "cheap", then you'd better expect "a new device every 2 years".