Beatmaker runs on iPhone and iPad, so its presets have to get from your computer onto the device. There are a few ways to do it:

• Finder (macOS Catalina and later): connect the device and drag the files across. Apple’s guide.
• iTunes File Sharing on older macOS versions. Apple’s guide.
• The Files app, through a cloud service such as iCloud Drive or Dropbox.

Each iOS app imports files a little differently. If the presets don’t show up, check the app’s own manual for how it imports files.