Hi KatNixCat
having looked in the past for a wifi adapter for my desktop, i could not find one that i was confident would support miracast it just does not seem to be clear on the device specs.
the adapter needs to be a Wi-Fi Direct CERTIFIED Miracast device.
i did however find a work around that meant i did not even need my desktop to be wireless. (wired connection PC to router, wireless connection router to tv)
most smart TVs that support miracast also support chromecast, by running either chrome or the insider preview of edge (minimised) i can cast my desktop to my television.
in chrome, click the three dots in the top right corner and select cast
it should find available devices, click sources and select desktop then click on the device (tv).