Hi Geshultz,
- Firstly, you can feed yourself with /heal although there is a 5 minute cool-down on it. [There is also a custom enchant on certain game-modes called implants that also keeps you fed.]
- Secondly, If you still want /feed to be added as a separate command you can post your suggestion
here for the community to up-vote if they like the idea and comment their thoughts on it. This will give your suggestion a better chance to be added to the server,
I hope this helped. Have a nice day/night!