How do rss feeds (such as rsshub) apply to your own projects?

beginners learn the concept of rss, although know that rsshub can get a lot of website content, but read a lot of related blogs are to recommend some rss readers for their own use,
if you want to make this into a function in their own app/web, (similar to instant? (what do I need to do?

Rss
Jul.01,2022
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