I'd suggest your drivers are messed up or the internal Realtek hardware is messed up.
You could try the Windows audio troubleshooter if you haven't.
For Realtek you only need out of the box Windows provided driver for that and it will work fine. That's all I ever use and no issues on any computer.
So in Windows Update find the other drivers section and see if it has a driver for RealTek there. If you see anything else just leave it alone as Windows will deal with them slowly on its own.
If there's nothing there then you will have to see if hidden devices in Device Manager shows up anything or attempt further to manually install a driver (you can alright click click and scan for hardware changes and see what happens). If the RealTek hardware can't be found in there (it should be found even without a driver) then it may have a physical issue. Although, you should try power cycling the computer or a BIOS update (and maybe reset) as they could potentially affect it and bring it back.
There's some other possibilities but I'm less sure if they'd actually do anything here at all and would waste too much time and some are too advanced.
Addition: I should add that the mic, the internal hardware, the application the mic is used in also can all cause your static issue as well. For the most part, to have better mic quality, an audio interface should be used such as a USB one. It offers better clean sound and separates it from the internal interference of the computer. The audio cleanup that applications use does a fantastic job for free but has various issues more than a paid for audio interface. But, that may be too complex for you as well.
Hope the best :)