It will depend on your shape.
If it is a complex 3D shape you will need a milling machine or a electro discharge machine.
If it is a simple square, rectangular, or triangular shape, you can do it with a standard chop saw with a special blade. This works really well.
If you need a round shape you can do it on a lathe.
Plasma cutters are not very precise, so I wouldn’t use that for anything you need any kind of precision with. A bandsaw is also good for certain shapes but metal cutting blades are a bit wider than other blades and you will lose some precision. You would have to cut over sizes and then use another tool to get down to the shape you want.
Unfortunately, the Glowforge will not work to do this. You would need a much more powerful laser for that much aluminum.