Question I cant install Realtek

realtek which ive linked was installed? i can guess it should

disable internet (unplug internet cable/disconnect wifi)

open device manager, and click on any device, u should see some extra icons will appear under menu (single left clicking on any device will do)
at top in menu click on Action -> Add Legacy Hardware
click Next, select second option (install hardware manually - advanced) -> Next
now scroll down until u see Sound, video and game controllers and click Next
windo will appear with two pages.
on left side under manufacturer, select Realtek and on right side select Realtek High Definition audio controller click Next, Next, Finish

now under soundcards u should see realtek HD audio which will still have code 10 (triangle with exclamation mark)

enable internet now

right click on realtek high definition audio controller and select update driver
it will search online drivers now and should install it, once its done, it will really need reboot now
Check for any hardware related error in event viewer:

Check if the audio services are started:
Click start, type services and open services.
Search for the below services. Double click on it to start and set it as automatic.
· Windows audio
· Windows Audio endpoint builder
If the services are already started, then restart the services

u may also want to open CMD with administrator rights and run following commands one by one:
SFC /ScanNow
DISM /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /ScanHealth
DISM /Online /Cleanup-Image /RestoreHealth