I use LMMS for making beats/midi. Make sure to get latest release. It could use some major improvements but it gets the job done most times. I use Audacity to fill in the gaps.
I've been using Juk as an mp3 player and I've been using Picard (MusicBrainz) for metadata. I just switched to Nicotine for downloading and it seems great so far. (Previously I was using yt-dlp but the new YouTube API is harder to use and scarier in terms of getting banned.)