How to use the C# SDK from a personal Unity project?

Hello,
I’m a recently whitelisted dev.
I have one main question: can I somehow connect a personal Unity project to OW (for my graduation research project) or does OW only work with registered games like Fortnite?
If I can connect: could someone please provide some sort of sample on how to use C# code with the SDK? I cannot make heads or tails of the “handle” variable in owgame_events_create()
Thank you!
OwGameEventsDllWrapper.cs