The Advanced tab allows you to set more advanced options. If you are not sure about their effect, you can just leave the default ones.

The Advanced tab
Archive backend:

Akregator currently only uses the Metakit database.

Article List
Mark selected article read after

Default is 0 seconds, which means that as soon as you click on an article it is marked as read. You can choose to mark any article as read after a specified number of seconds.

Reset search bar when changing feeds

This will clear the search bar when you change feed.