Perhaps you should just leave things as they are unless you can determine that the presence of both the integrated video card and the add-on card is causing a performance problem. On the other hand, you might try this. Open Device Manager, right click on the integrated video card, i.e. display adapter, and select Disable. This will leave the item in Device Manager but it will be marked with a red X.
And, yes, you could uninstall the integrated video card in Device Manager. But, first, I would disable it, as explained above, and verify that your system runs normal with it disabled. However, you may find that, if you uninstall it, it will reappear when you restart your computer.
And, as I said in my previous post, your BIOS may have an option to disable onboard video.