Hi there, I want the webpage of the tag to be a list with all my posts that contain the tag. Something like this:
https://mousikobostani.github.io/post/archive_alphabetically/ and not like who is it now:
https://mousikobostani.github.io/tags/ήπειρος/
Thanks in advance
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Let us see your code
Include a link to the source code repository of your project, because we really need the context of seeing your templates and partials to be able to help you. It is trivial to do a quick git clone on your repo, then run hugo server in your project, to help you out. On the other hand, recreating your code from screenshots, or sort of guessing at it, is not.
If you can’t share your repository for whatever reason, consider creating a dummy repo that you can share, which reproduces the problem you’re experiencing.
Thanks for answering and sorry for the luck of information and my bad english 
Here is my code: https://github.com/igoumeninja/xoriopalio_hugo
No problem.
mkdir layouts/_default
cp layouts/archive_alphabetically/single.html layouts/_default/term.html
Then edit layouts/_default/term.html, changing this…
{{ range where .Site.RegularPages.ByTitle "Section" "post" }}
<li><a href="{{ .Permalink }}">{{ .Title}}</a></li>
{{ end }}
to this:
{{ range .Pages }}
<li><a href="{{ .Permalink }}">{{ .Title}}</a></li>
{{ end }}