How to connect a display to a discrete graphics card on a laptop?

Question

Video cards

good day to all. perhaps my question will seem complete nonsense and unworthy of attention, but I did not find information on the Internet and therefore I turn here.
there is a body - an Acer Aspire 3 laptop and two video cards: the one that is discrete, and the one that is marked as "basic video adapter" in the device manager.
when I try to open the settings of the video card (Radeon R5 m435), it gives an error: connect the display to the video card
. There are also a lot of brakes and lags where they should not be (games that ran without problems on my old PC, started to hang wildly on this computer and slow down sometimes on the boot screen even after resetting to a minimum).
When you disable this very basic video adapter through the manager, when you try to enable the settings, an error also pops up, but it’s different. Sample text: "drivers installed incorrectly"
OS: Windows 8.1 64 bit, the drivers are the newest and downloaded from the official AMD website. I'd be grateful if someone could help me out!