I'm not sure if this framework script will work for my guns?

I have very basic scripting skills and I'm not asking for scripts I just wanna know what kind of categories I would need to learn so I can make a good fps, take phantom forces or last strike for example, of course I can't make one as good as those but I would like to make a fps that is good and playable.

I can do something like this

local setting = {}
local cf = CFrame.new
local ang = CFrame.Angles
local rad = math.rad
local random = math.random
local flr = math.floor
local cam = workspace.Camera.CurrentCamera
local player = game.Players.LocalPlayer
local guns = game.ReplicatedStorage.Guns

That's pretty much what I will make my gun out of that is all the things I will be using and I'm not sure if that's gonna work. I'm not sure what springs do but I want to make my whole gun using CFrame and not springs. Truth is I really don't know how to use any of those I've have seen protoduction's fps tutorials but I want to have my own but I kinda took his example please help me if you can.