If you want to play without Steam to avoid mod updates or allow non steam players to join your server, you can use these steps to connect.
Note: You will need to manually install mods to the file manager and the server will appear offline in the control panel, as we use Steam to check if it is online or not.
1. Open the File Manager
2. Navigate to /server-files/
3. Right click server_start.sh
and click Edit
4. On line 17, add -nosteam
LD_PRELOAD="${LD_PRELOAD}:${JSIG}" ./ProjectZomboid64 "$@" -nosteam
5. Restart the server