Need help on how to start my first project


So I want to create a game, I want to create a monster hunter/dauntles/borderlans type game. Its an fps game thats about hunting monsters just like in monster hunter and dauntless but with guns, kind of like borderlands. I watched several tutorials but these are mostly about zombies and fail to include multiplayer. So thats why Im asking, where do I start. I dont know if i should pick a tps or fps template because i want to make this multiplayer, and picking fps will only show me the arms. I want to know what I should do first, make the weapon system, the main menu, the hud, the health systems. I really don’t know, in the turorials I watched they all make a character that spawn with a weapon, but I want to implement a character/class selection, I don’t want everyone to spawn in with a basic AK-47. I’m fully aware this is quite a handful to do by myself, but im prepared to spend months or even years on this project.

What you are asking for has multiple answers, it depends the way you want to deploy the game in fact, as you said, is a very huge development so maybe when you finish UE is going to have more capabilities that help you to achieve your goal.