Edit Blog, moving on or tryig to.

Hi. I am new to MVC Core. 
I have been attempting to get an edit blog working.
The code is at - https://github.com/DotNetDS/CoreMVC10052017a.git

If I type in http://localhost:50260/blog/edit/1,2,3 etc. It displays the correct record.

In Views/Blog/Index.cshtml line 30 I have <a asp-action="Edit" asp-route-id="@post.Id">Edit</a>.
Which is obviously wrong.

In Views/Blog/Edit.cshtml line 28 I have <button type="submit">Edit Post</button>.
Which is obviously doing nothing. i.e. does not update record.

Thanks,