There are many ways that you can go about searching for a site's, blog or news RSS feed link.
These 3 videos offer a few quick ways you can go about your search:
In this video, you will see that on some websites, RSS feeds are readily available via the RSS feed icon. This is usually found with social media icons or near the bottom right corner or top right corner of the page. An RSS feed icon looks like this . Many times, major news sites will have multiple RSS feeds depending on what category the articles fall under i.e. National News, World News, Business News, etc.
In this video, you will see that often you can input /RSS or /feed after the web address to access the RSS feed.
In this video, you will see that you can download an RSS finder extension in various browsers such as Google Chrome. When visiting a website, you can click on the finder icon to pull the RSS feed. Other browsers have similar tools that can be accessed which you can learn about here.