In short Yes, UE4 is open source and you can do anything.
You can check out this tutorial about how to build your own dedicated server.exe in UE4:
Nonetheless, since you know nothing about unreal, it will take you a while to actually learn how to use it, how to make a game, how to make a multiplayer game, and eventually you to make your dedicated server.
It’s doable, and you will have the community to support you.