How to Create RSS Feed in Sitecore?

Before going to start creation process,

We will go with traditional way (Safe and Solid) means first What, Why and How ?

1. What is RSS Feed?

is Rich Site Summary responsible for the delivery of continuously changing web content. For Example: Suppose you have so many sites, portals and social media platform where you want to update your latest content automatically listed then RSS come into the existence.

So it's really amazing technique for Content Publisher.

2. Why to use RSS Feed?

Why, good question.
Suppose you have content related to:

Latest Events
Latest News
Latest Blogs
Latest Offer Posts
etc..

which you want to publish automatically on the other sites, platform then use RSS Feed.

3. How to create RSS Feed for our Sitecore Instance?

Now come to last but not least, So let's start creating RSS feed in Sitecore.

Oh I forgot one important thing, Let me explain here - "to publish latest content automatically using RSS on other sites you need RSS external URL"

for example: YahooNews (http://news.yahoo.com/rss/)

Now In sitecore at which path you wanted to put your RSS item means
here I will put my RSS item at home level So that every item will be listed.

now here at this path will create RSS item of template type "/sitecore/templates/System/Feeds/RSS Feed"

after creating RSS item give the input for fields

like the link of the item to list all the descendants, Link of the instance

now design RSS for the item which we want to list to the RSS genreated link's content.

after this, publish RSS item and also item for whom we design RSS(here will publish home item bcz we set RSS design for this item).

and hit /run on the live mode and yes we achieve this.

Have a Great Day, Let me know if any issue will my pleasure!!!