For an e-Book submission I must use style headings to indicate sections (title, copyright page, dedication, chapter headings, acknowledgments). I have been told to use Heading 1 for main title and also for copyright page and dedication, but the font that is appropriate for the title is certainly not appropriate for the copyright page. I could use Heading 2, but that is what I am using for chapter headings: bold, centered, and again of a size not appropriate for copyright line. Can you change the setting for a heading and have it apply only to that instance, without all the headings of that number changing as well? Note that I may use only Heading 1, Heading 2 and Heading 3, and they must be used in order.

Yes, you can.

Directly format the text you want to look different. Select it and apply the font, size and weight you want. If this changes everything in that heading style, use Ctrl+Z (undo) and then modify the style to not automatically update.