A Blogspot makes a sitemap automatically whenever you published any new content into your blog post page. You do not need to get any third-party tools. But you can’t customize your site-map manually because it’s generated automatically by Blogspot. Blogspot sitemap is important when you submit a site into Bing Webmaster Tools or Google search console.
Your site will easily index on google and users can see your post on google result as soon as possible.
This one is an example of your post sitemap
This one is an example of your page sitemap
Related More, you can search your sitemap for pages and posts, just by changing www.examples.blogspot.com name to your blog name URL address. If you are using a paid domain, then your website sitemap will be shown like this www.examples.com/sitemap.xml locations.
Another way, you should note that the Blogspot sitemap is changed automatically in a queue number of blog posts. Look out this guy sitemap. There are showing multiple sitemaps into the main sitemap.
/sitemap.xml?page=1 /sitemap.xml?page=2 /sitemap.xml?page=3
So at the start, when your all number of blog posts is less than 499, then your all posts links go to the main homepage sitemap i.e.
www.examples.blogspot.com/sitemap.xml. But when someone posts his 502 posts, then, his main sitemap will change i.e. its first 1-501 post will be listed out in
www.examples.blogspot.com/sitemap.xml?page=1, and another 500-1000 listed out in
www.examples.blogspot.com/sitemap.xml?page=2 and so on. And all these sub-sitemap pages will point to your main sitemap
So whenever you need to add a sitemap somewhere like Google webmaster tool, then you only need to apply your main sitemap i.e.
www.examples.blogspot.com/sitemap.xml. You can also submit (add) your any site page sitemap
www.examples.blogspot.com/sitemap-pages.xml if you have many important pages which are the best.