I have a LAN cable connection on my laptop. In addition to that, there's still a Thunderbolt connector available, for which I also have a LAN cable adapter here. So I can also get LAN via the Thunderbolt connector. Do I then have the option of operating both LAN ports with a total of two LAN cables, so that the download can theoretically be doubled?
That depends on your router… Not the number of cables…
I could connect two LAN cables to it
Yes, and… If you connect two hoses to your faucet, water will no longer come out of the pipe.
No. Normal Lan cables create 1Gb / s. Ie. Even if you have a 1Gb line, it is completely transmitted by a Lan Lan cable.
But the individual performance is definitely sufficient. It's like turning the tap on more. Is it then possible, or does the laptop accept a maximum of one LAN connection?
What speed have you booked with your provider?
Your router is already the fully turned on tap…
Think about where the bottleneck could be in your system?
This is the strangest question I've seen in a long time. But to answer it: no.
To explain this in detail would be too complex, each connection gets an IP address, downloads can't be routed to 2 IP addresses at the same time. So the download would only ever run via a connection, i.e. A LAN cable. The opposite even occurs, depending on the router, the speed per LAN port is then limited. This is simply due to the fact that the router (unless otherwise set) tries to provide each Lan port with the same speed / to hinder the maximum possible speed without other Lan ports. In the stupidest case, you can even reduce the speed because the router thinks there are 2 different connections.
But the simplest explanation is this: a single LAN cable can transmit more data than your Internet connection can bring. That means you can only speed up the download if you book a faster line with your internet provider. A single LAN cable is not even used when 1 Gbit (1,000,000 Mbit) runs over it. Fun fact: The speed in Germany can usually not even be reached with FTTH, i.e. Fiber into the house.
Can: yes. But what is then has already shown the coupler cassette. Your PC / laptop and router link aggregation should be able to do this, but this is rarely the case. And even with a 1GBit connection (website) you will only achieve as much as the remote station can. And most of the time there's the brake.