How force login screen on particular pages & one of the category archives?

you can make pages “private”, thus forcing a password
https://codex.www.ads-software.com/Content_Visibility

Thanks Samuel.
Is there a way to force the login on a particular archive page too?

maybe this
https://www.ads-software.com/extend/plugins/members-only/

Almost, but I only want to force login on one particular category archive page, not the whole blog.
Any other suggestions or hard-coding I can do?

Thanks again!