Installing two different versions of Windows via BootCamp? I am using a Mid-2013 MacBook Air running macOS High Sierra. I have installed Windows 10 on it using bootcamp.

Can I also install Windows 7 on it using BootCamp and run it alongside Windows 10 and macOS High Sierra? i.e., while starting up, I can hold down Option and select between the three installed OS.
I tried and found that you can’t install two different operating systems. When I tried, I came to the installation screen and nothing responds.