TBRSS supports all feed formats: RSS, Atom, RDF, and variants thereof.

You can add a feed with its address:

https://www.tbrss.com/blog/atom.xml

Or with the address of a page that links to it (through link elements, or inline):

https://www.tbrss.com/blog/

You can also use just part of the address:

tbrss.com

Or the name of the site:

TBRSS Blog

Or the topic of the site:

tbrss