The Wikipedia page for the term web feed is pretty helpful for getting a general understanding.
This website delivers a feed in the RSS format that can be subscribed^* for free by using various app(lication)s and add-ons.
For example such a feed reader is also part of Mozilla Thunderbird.

For each popular operating system a number of feed reader apps exist. The website www.rss-readers.org can be used as starting point for your search.
Alternatively you may find a suitable tool by using a search engine (such as www.startpage.com), the app store of your mobile device (for example Android, iOS), or the add-on store of your browser (for instance Firefox).

^* This website does not deliver notifications about updates. Instead the site responds only to queries of the feed readers (pull technology). Therefore no registration is required.

The RSS feed is delivered from URL nicht-verhandelbar.de/tweets/rss/feed.xml

After configuring the feed reader it checks that XML file for updates in the default or manually set interval.

The list of current links can be found also here.