Blogger comes with some goodies, like the atom feed URL, which can be used to generate sitemap for bloggers.
  1. Sign in to Google Search Console.
  2. Select the Blog from the left hand side.
  3. Click on Sitemaps link.
  4. At the top of the page with title "Add a new sitemap"
  5. Add the below code in the text field.
atom.xml?redirect=false&start-index=1&max-results=500
Google Search Console

Example :

https://webdevpedia.blogspot.com/atom.xml?redirect=false&start-index=1&max-results=500
Press “Submit Sitemap” button.