I just don't quite understand how to configure k2 seo,
please see the attachments, where can I find the tutorial which explains how to configure k2 seo,

in addition, any advantage of k2 seo?

Hello,

The SEF character replacement, will convert non UTF-8 characters to their equivalent ones.
As for the advanced SEF section which is optional, you can select the prefix (the slug) for each piece of content in order to replace /component/k2/ part.