How can I display 13 selectable items on a Mobile First responsive webpage?

1. How many breakpoints should you have?
2. What are breakpoints for viewport responsive device?

How many breakpoints should you have?

While there is no universal set of breakpoints or best practices, you should use at least 3 breakpoints for the most device flexibility (see illustration). When designing for specific breakpoints, consider the content you have. Don't build media queries for devices, built it for content.

What are breakpoints for viewport responsive device?

In responsive web design, viewport breakpoints are browser dimensions (usually just widths) that set the active range of a given media query. Once the browser dimensions are within that range, the styles associated with that media query will apply.