Updated 2 August 2023 (15 March 2023)
To create an RSS feed from scratch, you need basic knowledge of XML and a general understanding of the RSS specification.
An RSS feed consists of a channel that requires a title, a link, and a description element. A channel usually contains several items and possibly also some optional subelements.
An item requires at least a title, a link, or a description, but may also have two or all three. An item possibly also contains some optional subelements.
I suggest that you start by creating the channel with the required elements and then add the optional elements where appropriate. And do the same for the items.
Here is an example of an RSS feed for my Dutch-English word of the day project. The content for the items is retrieved from the website database.
In order for others to find your RSS feed, you can make it discoverable on your website in the following ways:
<head></head> tag of the HTML code of your website:
<link rel="alternate" type="application/rss+xml" href="./feed.xml"
title="Feed name">