Number of items that appear on a page

Only with a plugin:
https://mattread.com/archives/2006/01/custom-query-string-27/

Thanks!!!!!! That sounds perfect. Appreciate it.

I just downloaded, installed it and activated it. But I’m not seeing how it can help set different number of posts displayed. I can see how it distinguishes section page from section page (that’s good), but not the section page versus the homepage. How do I do that?

I don’t know what do you call “section page”, sorry.
In your admin panel you go Options > (and submenu) CQS.
Then you select the different conditionals, like:
is_archive (for monthly listing)
is_category (for listing posts in a category view)
is_home (for the main page) etc.
For each set (type) the number of posts you want, set the order and click ADD.

I’m calling a page a “section page” when it’s anything OTHER than the homepage. I need to set a limit for the number of blogs on the homepage, but no limit (or a MUCH larger limit) for all section pages. Does that plug-in do that? I couldn’t see in its page listings anything that I recognized as the homepage.

Your problem is that you try to invent new terminology ?? instead of using what is widely accepted in the WP documentation… and causing frustration for both of us.
Especially do not use “page” since that’s the most confusing thing is WP (though it’s not your fault).
In WP you have a view of posts on your homepage (mainpage, entry-page) – then there is “archive view” when viewing monthly listing; there is “category view” when seeing posts in one category etc.

Yes, this plugin does exactly what you want, just read what I posted above and look at the options in the admin panel.
You want 5 posts on homepage? Set “is_home” to 5.
Want all posts in monthly archive? Set “is_month” to -1.

What is so complicated?

Thanks!