In a Writer document I need to change the layout of several pages from vertical to horizontal. How can this be made?
Thanks in advance for your help.
You need to add a manual page break with style changes before and after the landscape pages. There already is a page style named “Landscape” or something similar.
There also is a help page about it. Thanks to Stanislav for pointing it out.
@mahfiaz - "manual page break with style changes before and after the landscape pages. " this was the important information. Thanks a lot!
Ah! You really do mean Insert > Manual Break... > (·) Page break + Style = Landscape. I was using CTRL-ENTER to put in a manual page break, then applying the style from the F11 dock, and I couldn’t figure out why it wasn’t working! Thanks for this. 
Hey, you are welcome A little cumbersome, but makes it sure that the content never drifts off to another page. Joy of editing long Word documents if anyone remembers.
The way to change the layout is actually not cumbersome and straight forward but I could not find the solution in Help. Now I place an enhancement request for Help. https://bugs.freedesktop.org/show_bug.cgi?id=76428
Feel free to add comments.
As noted by Stanislav in the bug report, there actually is a help page about this: Changing Page Orientation (Landscape or Portrait) - LibreOffice Help
Format >Page >Page >Orientation >Landscape.
This changes the currently page’s style to landscape, which likely is the only page style used and effectively makes the whole document landscape.
This is what I needed to know though.