Hi, apologies, Comment wasn't supposed to be a Main CTA - it is already under each post. I removed that option from settings now, please choose something else. Posts per page seems to work on your site, maybe refresh. The pagination is automatic on that theme, posts are loaded on scrolling. 

 Ah ok. Posts per page, I would like to not load all as scrolling, I would like to see just 20 and have manual pagination. 

 This theme doesn't support manual pagination, I think some other themes do, i.e. Liebling.