Can you make a part from Vector 3's??

Attempted a simple version to help understand my question

Let's say I have an empty list and this local script in a tool

local builtList = {}
local tool = script.Parent
local player = game.Players.LocalPlayer

When you click with the tool the Position(rounded) gets added to the list.

tool.Activated:Connect(function()
	local vNode = player.Character.HumanoidRootPart.Position
	local RX, RY, RZ= math.floor(vNode.X + 0.5), 
				      math.floor(vNode.Y + 0.5), 
				      math.floor(vNode.Z + 0.5)
	local RoundvNode = Vector3.new(RX, RY, RZ)

	table.insert(builtList, RoundvNode)
end)

Pretty simple. Now what I am hoping is there is a way to create a part/region/something that can be created from those nodes.

An example would be if I had a builList like above that was made up of (4) Vector3's {A,B,C,D} and these 4 Nodes created a square. Is it possible to create a part or region or something, using those points as the nodes? (could also be a triangle, or any completed polygon so thinking Region3 is out of the question)

To be clear, I can make lines from Node to Node, I'm looking to create an area inside all nodes in the list. (The list in my actual problem will always consist of only nodes that make up a completed area, with lines connecting each node) Just looking to fill, ideally with a part.

In a perfect world, I would like to create a part that is the size of the shape the nodes make.

Thank you