Internet only works only when a certain other PC is on in the network, what should I do?

I only have an internet connection on my PC (Windows, latest version) when my mother's laptop (MacOS, latest version) is on. As soon as she puts it into sleep mode or shuts it down, my internet connection breaks down. I use a direct LAN connection and they have a docking station with a LAN connection. If necessary, I can also provide more information about the hardware software. I haven't found any current entries on Google yet.

Then the settings are incorrect. The way you describe it, you get the signal from your mother's PC and not from the router.

You have to connect your PC to the router using a LAN cable.

Can you explain in more detail how the network is structured?

In other words: Which router and how the cabling was done.

Do you know where to set that? In the router settings or on my PC?

I have already connected my PC via LAN. I don't quite understand what you mean…

Please specify the settings of both PCs, ip, subnetmask, etc.

Connect this LAN cable directly to the router.

The computer must be able to access the Internet independently of your mother's laptop.

The router is not connected to the laptop's docking station, is it?