Welcome to WikiTree, Steven! I wish you all the best!
As far as Ancestry.com images, it is not a matter of copyright law but contract law. Many, if not most, of the images their are not copyrightable by them because of the age of the documents. However, when you became an Ancestry.com you accepted their terms of service which includes information about how their images of those documents may be used by subscribers. You should review the terms of service and decide. Scroll down to the very bottom or your Ancestry.com homepage for a link to the document. People here have varying opinions about what the terms of service allows and limits. However, for almost all of their images, Ancestry.com provides a "shareable link." Look in the tools at the right-hand side of the image to find this link. The WikiTree help page Peggy provided will explain to you how to include that link in your source citations.