In MVC5 there is @Ajax.ActionLink that is useful to update just a partial view instead of reloading the whole View. Apparently in MVC6 is not supported anymore.
@Ajax.ActionLink
Use tag helpers instead and make sure to include _ViewImport in your views folder.
Note: Make sure to use document.getElementsByName if there are several links pointing to different pages that will update your DIV.
Example - Razor Page
Session Session Some Default Content