My preferred RSS Feed reader is currently https://miniflux.app/ – It’s open-source, simple, and has great keyboard shortcuts. Also, the developer provides a cheap hosted version if you don’t want to run it yourself. It also has a really nicely done PWA to install onto a phone using the browser.
I used to use feedly, but it has started putting ads all over, doesn’t seem to support open-source at all, and restricts access to some RSS feeds, like reddit pages. I would not recommend using feedly.
These are some of my favourite RSS Feeds:
Linux / Tech Blogs
GNOME Shell & Mutter – https://blogs.gnome.org/shell-dev/feed/
Kev Quirk – https://kevq.uk/feed/
ServeTheHome – http://feeds.feedburner.com/ServeTheHome
Phoronix – https://www.phoronix.com/rss.php
PINE64 – https://www.pine64.org/feed/
Adventures in Linux and KDE – https://pointieststick.wordpress.com/feed/
JRS Systems: the blog – http://jrs-s.net/feed/
AnandTech – http://www.anandtech.com/rss/
CommitStrip – http://www.commitstrip.com/en/feed/
xkcd.com – http://xkcd.com/rss.xml
Poorly Drawn Lines – http://feeds.feedburner.com/PoorlyDrawnLines
Order of the Stick – http://www.giantitp.com/comics/oots.rss