How to submit sitemaps to Google?

Submitting your Sitemaps to Google
This is what you need to do after creating sitemap,
make sure that you create the sitemap of the similar
theme as shown in the above step; otherwise you
cannot submit it to Google Search Console.
Submitting Google is carried out in 2 steps:
Step 1: Confirm your website with Google Search
Console. Make sure that you complete this step
before jumping to step 2.
Step 2 : Add Sitemap to Google Search Console:
After successfully confirming your website with
Google Search Console as shown in the first step, go
to
Google Search Console=> Crawl => Sitemaps
After that, look at the top right of the screen, click
Add/Test Sitemap
Add your sitemap, notice that you should only add
the tail of the sitemap. For example, the sitemap that
I created by Yoast SEO has such a tail as
sitemap_
index.xml, just add this tail, no need for the entire
link because Google Search Console will provide the
link beforehand, you just need to click
Submit.
You will be notified as Item Submitted, which
means your sitemap has been submitted to Google
Search Console, you can click
Refresh the page to
check the sitemap’s state:
If there are no additional errors, it will display like this.
Hence, you succeed to add sitemap to Google Search Console.

https://www.quora.com/How-do-you-submit-sitemaps-to-Google