A proper website has tree structure. Any upper node accumulate the weight of sub-nodes.
Blog category combines the weight of posts belong to it. Ecom category combines the weight of items’ pages. Photo gallery combines the weight of photos associated with it. Anyway it should. But very often it would not.
The primary means of passing a weight to upper level page is a link to it placed at each lower level page. And vice versa – a link to each sub-page should be placed at a category page. The both links should be visible – at sub-page as a breadcrumb text, at category page as an ordinary link.
In terms in Google ranking it means category page will be ranked higher than a page of category item by the same keyword. You may check if yourself typing
site:thenameofyour.website SPACE thetargetkeyword
in Google search box. The 1st page as a rule will be a domain itself because it accumulates the weight of all website pages.
Ideally the target keyword used as a link anchor text. Say for a page about short ceramic knife anchor text of link to category will be ceramic short knives. The more a keyword is used in internal links the higher the website will be ranked by it.
Lifehack! If your website includes a blog the best way to increase a weight of website page is to place a link to it in blog post.
There is a free online tool allowing to check internal linking called megaindex – I will tell about it the next time.