The engine ships with an inventory and weapon system, modelled loosely on Garry's Mod. It gives you pickups, slots, weapon switching, ammo, shooting and reloading without you having to build any of it.
There are three components:
A working gun needs no code at all. Put a BaseWeapon on a prefab, fill in the properties, and it shoots, reloads, runs dry and plays its effects. You subclass when you want it to behave differently.
Everything is networked. The host owns the truth, and the holding player predicts locally so firing feels instant.