Minecraft 1.12.2 modpack server combat system?

Hi, I have set up a Minecraft Server Forge 1.12.2 and want to turn off the combat system does anyone know how I do this?

Without mod or plugin not at all.

Do you know a mod for it?

Unfortunately not…

Try the Mod "BetaDays" with this you can restore many mechanics from the old versions. Of course you can also set that only the fight system is blocked.