Because nPlayer is an Android application (APK), you must use an Android emulator to run it on a Mac.
: Grant the app access to your storage so it can scan and play your local media files. For macOS (M-Series or Intel)
Select your nPlayer-v1-7-7-7 file from your Mac's downloads.
: Locate your nPlayer-v1-7-7-7-apk-patched.apk file and tap it to begin the installation.