@skumar1st
The Yoast plugin automatically adds a “noindex” tag to all feed URLs, since they don’t provide useful content to your site and should not be in the search index. These type of URLs are not added to the sitemap by the plugin either. However, it’s normal that they are excluded from the index and should not be a cause for concern.
RSS feeds are automatically generated by WordPress. WordPress creates feeds for almost all items on a site, including posts, comments, etc. You can find more information here. If you don’t have any use for RSS feeds on your site, you can find more information on how to disable them here.