1. Press Win + R keys together on the keyboard to open the Run dialog. Type dxdiag in the Run box as shown below:
2. Click the button "Save all information..." to save all the collected information to a text file:
3. Enter the file name and save the file to the desired location.
4. Now, open the saved file with Notepad and look for a line contains the "Miracast" portion. You can press Ctrl+F to open the Find dialog and type: miracast. If it says "Miracast: Supported" in the file, then it means your PC supports the Miracast wireless streaming feature.
Note that Windows 8.1 and Windows 10 only have the ability to send/broadcast your screen using Miracast to a receiver device. But it does not have the built-in ability to receive Miracast signal from another device out-of-the-box. It only has the necessary APIs to support this, so to receive using Miracast, you must install some app on Windows which has this ability.