I just do this. Update the ubuntu line every 2 years or so. This runs as a cronjob on my synology with the working directory set to a directory that the Synology "Download Station" is watching. It picks up the torrents and does its thing. I come in every now and then and clean out the dot releases. It's not the best but it's not the worst either.

  #!/bin/bash
  wget -nH --cut-dirs=4 -r -l1 --no-parent -R "*.tmp" -A "*.torrent" https://cdimage.debian.org/debian-cd/current/amd64/bt-dvd/
  wget -nH --cut-dirs=4 -r -l1 --no-parent -R "*.tmp" -A "*.torrent" https://cdimage.debian.org/debian-cd/current/amd64/bt-cd/
  wget -nH --cut-dirs=4 -r -l1 --no-parent -R "*.tmp" -A "*.torrent" https://releases.ubuntu.com/22.04/
  rm *-DVD-{2,3}.iso.torrent debian-mac-*.torrent *.tmp *.loaded