How to stretch an image across 2 monitors?

Question

Monitors

I understand that the topic has already been discussed many times, but I have not found an answer.
The fact is that I want to connect an additional 2 external monitors to my laptop. But, if I turn on 1 in hdmi, the other in vga, they don’t want to work together. As I understand it, on my laptop (dell inspirion 7720) this is not possible.
But here is the question. Why can't I plug in some magic splitter that will request 3940x1080 from a laptop and output 1 fullHD on the left and another on the right. Either a regular splitter, but also programmatically make it give more, and set up image scaling or something similar on monitors so that each one shows its own part of the screen. MB there are such solutions already. I want Windows to think that this is 1 monitor connected, but in fact 2 were connected
PS I bought a monitor, but I forgot to think about the connection.

Answer 1

Yes, the laptop does not support two additional monitors. It is impossible to split the output from one video card to two monitors, everything is not so simple.

Answer 2

I don’t know anything about “magic splitters”, but I saw additional video cards connected via USB on Ali. Of course, not ordinary USB-2.0 is desirable here, but blue USB-3.0, which are 10 times faster.
And when you have as many video cards as you want, then stretching the image of the common Desktop and windows on it will no longer be a problem.