local Mag = (script.Parent.Center.Position-Player.Character.HumanoidRootPart.Position).magnitude
and if needed:
local Mag = (Door.Center.Position-game.Players.LocalPlayer.Character.HumanoidRootPart.Position).magnitude
Parent.Center only accepts one part of the same name, however I need it to accept all parts of the same name. How do I achieve this?

5 comments
You can use :GetChildren() to get all the children of Door, then use a if statement to check if it has the name "Center." After that, you can put them in a table and do the rest of your scripts.
I'm very sure you can't just get all the children with the same name by just doing Instance.Instance. You have to at least use a iterator or something to get all the children, as I stated.
I don't think there's any other way.
loop it and see if its name is Center then it will get all results
Do you want to teleport to the centre of all parts named lk'e that, or just to the centre of each part individually?