Miracast compatibility for desktops is complicated. You will need a compatible graphics card and wifi adapter. It is such a pain to find out if a particular device is compatible since it is usually not listed on the manufacturer's page. There is also no exhaustive listing on the web so you may have to take a gamble and hope that the device you purchased is compatible. You can try running
Get-NetAdapter | Select Name, NdisVersion in powershell. If the NDIS driver version is 6.3 and above, the wifi adapter should be compatible. No guarantees.
I have managed to get Miracast to work on a Nvidia Quadro P2200 and a RTL8812CU wifi adapter. Since some webstore listings do not specify the chipset, this is exact listing which I purchased.
Miracast will create a Wifi Direct connection between the 2 devices, do take note that the wifi adapter I linked does not have an antennae, it may affect the signal strength. Both my devices are quite close by and I have not experienced any stutter even when streaming videos in HD. I have not been able to get Miracast over Ethernet to work since my receiver does not support a wired connection. That is one potentially route you can take if signal strength is a concern.