I’ve tried several online news readers, and my favorite is Inoreader. Especially when used on an iPad or other tablet computer. Inoreader has tons of settings and options, so all your RSS feeds can be grouped and filtered to your liking.
If you want even more customization options, you can use apps like Fiery Feeds as an Inoreader client.
In effect, these tools enable you to read a “newspaper” comprised entirely of topics you are interested in.
And when you find an article you want to keep for future reference, you can forward it to another app (on an iPad or iPhone, this is done with the share sheet). Do you remember when people used scissors to clip new articles, and envelopes to share them?