It’s not obvious, but you can add your *.wordpress.com sites to Google’s Search Console.
You go through the regular process of adding a site, and pick “HTML Meta Tag” as the verification method.
Copy this tag into the WordPress.com dashboard.
The location is buried a few levels down. Select “Marketing” in the My Sites menu.
Then select the “Traffic” tag.
Scroll down, and there’s a field to enter the code.
Most other pages explain how to use Yoast or other SEO tools to set up the tag, but those plugins aren’t available for free WordPress.com sites. You probably had to dig through results to find this page.
If you liked this tutorial, and found it useful, do the “SEO” thing and link to it, so it’ll get better ranking on the engines. Thank you for your support.