I’ve begun a question and solved it already, so I am writing a how-to that will create a page with a top two-column section and finish the page with a bottom single column.
In LibreOffice Writer, here’s what I want to accomplish: Top third or so of the page is 2 columns listing instructions for use and membership dues information, finishing up with one full column with a couple paragraphs and the membership form to finish out the page.
Begin by Formatting the Page (Format menu) as a 1-column page.
From the Insert menu, insert a Section (Section 1) and define its column layout as a 2-column section. Three choices here: 2 equal-width columns; narrow left and wide right; wide left and narrow right. Set styling and other criteria as desired.
Enter the left column heading, and text as desired.
Insert manual column break from the Insert menu.
Enter the right-column heading and text as desired. If a column divider bar was requested when formatting this Section, that divider will extend to the end of the longest text column.
Insert Section 2 from the Insert menu and define as a single column.
This new Section defines the end of the first Section and takes up the entire page width.
Adapt these instructions by defining the first section as a single column or three-column Section, for example, for different layouts, and of course, you may add a third Section.
Adapt these instructions by beginning with a 2-column page definition in the Format > Page menu item. You may, for instance, place a narrow left column at the page level and enter various splits of one column or two equal columns via use of Sections in the wide right column.
I hope this is of value to someone.