In the meantime, a friend has a release 11 that I can play around with and start becoming familiar with the program.
Is this a good idea? Will I have to re-learn everything when I purchase the newest version?
Welcome. This is a great idea - whatever you learn in 11 will be all but identical in 12. 12 primarily added new features, rather than changing old ones. See the AC 12 new features page on the GS web site.
One of the forum moderators
AC 26 USA and earlier • macOS Ventura 13.4, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB