Toivo theme – divide the page in 4

Hello everyone. My question relates to Toivo Theme, page layout.

The page for Testimonials (https://foxland.fi/demo/toivo/testimonial/) shows four pieces of text divided by dotted lines.

Q1: How is this done? Via plugin/theme/template …? How can I implement it too, if possible without modifying theme files.
Q2: Can the page be divided in more than four pieces (say 8, or more?)
Q3: I understand that there are two options for inserting round photos in a page (as in the link above, small round pictures of people’s faces) : by modifying the CSS file, or by a plugin. If, indeed, both are possible, which do you recommend?

I guess from your answer I will also be able to infer whether this sort of page layout is avaialable for other themes than toivo.

Thanks in advance, your help is much appreciated.