I bought a gaming laptop from captiva and when I start the PC I don't have to install things. I don't have a normal start screen?

How do I configure my gaming pc correctly

I think you probably have to install Windows. You need a USB stick and another PC, otherwise you can look it up on youtube.

Uh, yes there's also that you first have to install Windows. It is the case with many devices that they are no longer completely pre-installed.

You then just answer the questions, set your username, data protection settings, etc.

How should the dealer know what you want there.