On the official Navidrome Linux install guide, they only provided steps on how to create a systemd unit and how to start the service using sudo systemctl.
https://www.navidrome.org/docs/installation/linux/
But for those using Linux distros without systemd like AntiX, Devuan, Alpine, Artix, MX Linux etc, you have to convert the provided systemd unit template and place it in another folder instead of /etc/systemd/system/ named navidrome.service.
Use the following template to create a SysV init script. Change <user> and <group> to your appropriate user and group for your server.
#!/bin/sh
### BEGIN INIT INFO