CFrame basics and how to use it?

I'm going to give you a small explanation here.

CFrame stands for CoordinateFrame.

You can use CFrams to change positions of Parts in three dimensional space.

Part.CFrame = CFrame.New(89,34,13)

If you wanted to add position to a CFrame, you would do so using Vector3

Part.CFrame = CFrame.New(89,34,13) + Vector.new(3,2,5)

You cannot compare CFrames like this.

 if CFrame.new(5,2,8) > CFrame.New(89,34,13) then --this won't work.
end

To compare CFrames, you would need to do it for a specific axis.

 if 40 > Part.CFrame.X then --this will work.
end

If you want to change the rotation of something.

Part.CFrame = Part.CFrame * CFrame.Angles(0,0,math.rad(30))

That's just the basics and a small part of CFrames. In reality, CFrames are a lot more complicated, but this is all basic roblox programmers would need to know.

CFrames are a complicated but very important aspect of Roblox development. You might be able to understand them better if you first learn about vectors and matrices, if you haven't learned about them in school already.

Take a look at this page on the wiki, I find it gives a very good explanation: https://developer.roblox.com/en-us/articles/Understanding-CFrame