3D Bezier Curves.

local part=game.Workspace.Part
local p0=game.Workspace.Part1.CFrame
local p1=game.Workspace.Part2.CFrame
local p2=game.Workspace.Part3.CFrame
local t=0
local function rot()
    if t<=1 then
        local pFinalX=math.pow(1-t,2)*p0.X+(1-t)*2*t*p1.X+t*t*p2.X;
        local pFinalY=math.pow(1-t,2)*p0.y+(1-t)*2*t*p1.Y+t*t*p2.y;
        local pFinalZ=math.pow(1-t,2)*p0.Z+(1-t)*2*t*p1.Z+t*t*p2.Z;
        t=t+0.005
        print(t)
        part.CFrame=CFrame.new(pFinalX,pFinalY,pFinalZ)
    end
end
game:service'RunService'.Stepped:connect(function() rot() end)