In order to enable the Blog RSS Feed link in Magento 2 Blog sidebar, please go to the Admin Panel > Stores  > Configuration  > Magefan Extensions  > Blog > Sidebar and find RSS Feed section.

RSS Feed

1. Enable or Disable the RSS Feed link.

2. Set the Sort Order to manage its position on the StorefrontThe higher the number of the position, the lower it will be displayed on the Sidebar.

3. Enter the Feed Title

4. Set the Feed Description.

Once you've finished don't forget to Save Config and Flush Magento Cache.

 Magento 2 Blog RSS feed configuration

5. Check the blog RSS Feed out on the storefront.

Magento 2 Blog RSS feed

This is how blog RSS Feed looks like:

Magento 2 blog rss feed