Silo structure for a small site

[Kang]

Is there any minimum number of pages (or posts) requirements to build a silo structure? I am currently using the Yoast plugin and for many internal links it gives error or sets up any kind of warning. So, I am wondering that whether my site is too small for a silo or not. It has 15 posts and atleast 7 pages in which 3 of them are basically niche category.