If you want to download music using Google services or your Android device, the method depends on whether you want official offline streaming or free local files. Google’s primary ecosystem for music is YouTube Music, which has built-in download features.

​Method 1: Official Offline Downloads via YouTube Music (Recommended)

​Google Play Music has been replaced by YouTube Music. If you have a YouTube Music Premium subscription, you can legally download songs, albums, and playlists for offline listening directly inside the app.  

​Open the YouTube Music app on your phone.  
​Find the song, album, or playlist you want to save.
​Tap the three-dot menu icon next to it.
​Select Download (alternatively, tap the download arrow on the album/playlist page).  

​Smart Downloads: You can also enable Smart Downloads in your settings, which automatically downloads up to 200 of your recently played songs based on your listening history.  

​Note: Podcasts on YouTube Music can be downloaded for free without a premium subscription.  
​Method 2: Finding and Downloading Free Music on Google Play

​If you are looking for free, independent audio files or apps that allow offline local playback without a strict subscription:

​Audiomack (Google Play Store): Audiomack is a legal music streaming and downloading app available on Android. It allows users to stream and download trending independent tracks, mixtapes, and specific artist releases for free, offline listening within the app.  
​Free Music Archives & Independent Sites: You can use the Google search engine to find platforms like the Free Music Archive or Bandcamp, where artists explicitly offer free, downloadable MP3 or WAV files. You can download these files directly through your mobile browser into your phone's Files folder.
​Method 3: Transferring Downloaded MP3s to Google Drive

​If you already have music files downloaded on a computer and want to access them across your Google ecosystem:
​Upload your MP3 files to Google Drive from your computer.

​Open the Google Drive app on your phone.
​Locate your music folder, tap the three dots next to a track, and select Make available offline. This downloads the file directly to your phone storage so you can play it anytime, even without internet.