Hello there, @reheftma ...
I am so sorry to see that your question has been sitting out here in the Community since October of 2020 without any response. After reading through your question, I did some searching here in the Community, and I found the following Guide:
How do I edit the details of a resource in Commons?
If you scroll down to the heading "Select Content Type", you'll see a screenshot and a couple short paragraphs that describe the options of "Template" and "Open Textbook". I've pasted in these paragraphs for you here (the blue highlighted text is my own doing, by the way):
You can label your resource as a template or open textbook content type. Content types help users more easily locate resources when filtering search results.
To select the template content type, click the Template checkbox [1]. To select the open textbook content type, click the Open Textbook checkbox [2]. Both content types can be selected for the same resource.
I hope this might help to answer your question about the difference between the two checkbox items, "Template" and "Open Textbook". And, to answer your second question, no, I don't think this would bear on the method of editing Commons content. These options are for helping in search results.
Please let Community members know if you have any other questions about this...thanks!