Here is a quote from “Newsboat” GitHub page:
Newsboat is an RSS/Atom feed reader for the text console. It’s an actively maintained fork of Newsbeuter.
This explains why everything looks almost the same when I open Newsboat.
About the migration, what I need to do is, run the following command to export the RSS URLs from Newsbeuter:
newsbeuter -e > newsbeuter.opml
And run the folloing command to import them into Newsboat:
newsboat -i newsbeuter.opml
After that, you can read in terminal again.