I did exactly what this directory said, and my part isn't showing up in the workspace. https://gyazo.com/d84828d9eefb515da499e7829b891d72
To put a part into workspace just do
local part = Instance.new("Part") part.Parent = game.Workspace
Make sure that is in a server script though. You could get more complicated than that if you wanted to make the position of it appear somewhere.
part = Instance.new("Part", game.Workspace)
some people do part.Parent = game.Workspace but my way is easier from my point of view and also if you wanna change the properties just do
part.BrickColor = BrickColor.Red()
the color can be anything or totally random theres also other ways to change the color but that was just a small example!