Blog menu displaying tags instead of post titles

As from the title: is it possible to achieve this? At present my blog menu opens a submenu where the items are the various posts. Let's say that three posts has "tag 1" and other three have "tag 2" . I wonder if I can have the tag 1 and tag 2 in the submenu, so when I click on "tag 1" I go to a page listing all the posts tagged as "tag 1" and so on...
I think I can achieve this with page collections, I have read the related documentation, but I couldn't find a clear solution to my problem (only a newbie and get confused about the correct setting of frontmatter)
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