Adding a saved section to a blog post

I am attempting to add a saved section (my email opt-in) to a blog post page but I don't have the option to add a section on a blog page. Any ideas on how to easily copy a section from one page to another (specifically a blog page)??

Thank you so much!

Blog pages are in effect one big section, you can edit how the content appears in the section and you add blocks such as newsletter, image, and lots of others. You click on edit section and then look for the plus sign at the top of a content box in the middle of the section, click it and all kinds of options appear in the menu box.