Let me try to be as clear as I can.
In another WordPress Theme "Responsive" by CyberChimps, they have a template in Pages that is called Blog Excerpt (Summary). If I select this template, the Page will show excerpt summaries of the number of blogs specified in WP settings. This is not about categories or tags. I do not want these excerpts to show on an existing blog post. This is a completely separate Page that is added just to show blog excerpts. Here is how this works on one of my Responsive Themes so you can see it in action (this site only has 3 blogs so that's all that show):
For my Raindrops website, I want to create a new page and tell that page that I want it to show blog excerpts only just like I did in my other website. The excerpts are pulled from the same data as is used for the home page by date with the latest first. I also want it to show more post than the WP settings which are set to 6 because that's what I want on the homepage. For this page I would like to show 15.
This is not about categories or tags. I don't just want to show the blogs from one category or tag which can be done now by selecting that category or tag. I want to show the post from all categories by date with the most recent first. Here is a preview of the blank page where I want these excerpts to show:
I cannot paste any code because I can't write code and wouldn't even know where to look to find it. From my experience in reviewing WordPress Themes, it appears that a Blog Excerpt (Summary) template that can be assigned to a page is a very common item.
Additionally, I cannot use Categories in the menus to do this because your Categories do not show excerpts, they show the entire post. Categories are supposed to show only excerpts of all the post in that category.
If this is too difficult to create, I will understand. I just thought it would be nice to have such a page.