If you're trying to scan just the your phone, download Lookout from the app store and it'll do the trick. If you really want to scan your phone from PC, simply install the required driver for your phone on your PC and setup a custom scan on your preferred anti-virus/malware software and select your phone's drive.
If you want to scan your android there are too many antiviruses available in the market which provides you best android antiviruses.
Or if you want to scan your phone with your pc you have to connect it via data cable and then open window defender and click a custom scan for your android.
Hope this will help you.
If I want to scan an Android device using my Windows 10 X64, is the anti-virus installed for the Windows able to find malicious files on the Android device too?
I mean, probably the worms and viruses for Android are different from Windows and the Windows AV is properly working on those Windows files only.