You are correct that anybody who is not prohibited from possessing a firearm can manufacture a firearm for themselves without a manufacturer's license according to federal law (with some restrictions and exceptions regarding the NFA). Not having a license shouldn't be an issue for you. But what you may need to check into are the federal, state, and local laws regarding possession of a firearm (and specifically a handgun) by someone under the age of 18. That does vary from location to location. The gun may need to be "owned" by your parents. Which may complicate who can "manufacture" the frame. The other parts are not an issue.
As far as the difference in parts for a 2011, the frame and pretty much all of the frame parts are common among the different calibers. However, many of the top-end parts are different. Those include the barrel, slide, extractor, ejector, firing pin, slide stop, and probably something else that I've forgotten. Also, the magazines are different (obviously).
Good luck in your adventure! I'd love to see the progress of your build as you go. For reference, it took me 2 weeks of evenings to make my first 2011 frame on my manual machines.