Get a node using the same category (taxonomy term) the current node is using
Add CONTEXTUAL FILTER (Earlier arguments) on CONTEXTUAL FILTERS section on views click add, select "Content: Has taxonomy term ID" and in "WHEN THE FILTER VALUE IS NOT IN THE URL" choose Provide default value. Choose "Taxonomy ID from URL" check "Load default filter from node page, that's good for related taxonomy blocks". It will create a related taxonomy.