How To Make Combat system like black magic 2

I am wanting to make a game similar to black magic 2, but I need to figure out how to set up the system, Should stuff be handled through folders and serverscripts, modules or even local scripts ? maybe could be done through both ? I really just need an In-Depth way to make and set up a system and what should be used to make one, and where things should be, I just want the gameplay/combat to as fluid and unbuggy as Black Magic 2’s

Black Magic 2 gameplay to get a feel for what im going for: /// Black Magic 2: Weekly Highlights #16 /// Roblox - YouTube

If someone could understand this and help me it would be a huge thanks !

if my discord is needed it is: moe.#1403