I think you are looking for this setting:
Dashboard > Settings > Reading
There is a tickbox for: ” Search Engine Visibility ”
There is also your robots.txt file which you should also configure.
Thank you Ross but that option is also already unchecked, you can check screenshot here: https://tinyurl.com/yhnxlzk9
If the option isn’t checked, the tag is coming from your theme or a plugin. There’s likely a setting somewhere similar to the WP one that you could untick.
If you have trouble locating the right place, narrow down the source by deactivating all plugins and switching to twentytwentyone theme. The tag will be gone. Restore your theme and plugins, one at time, until it reappears. The last activated is the culprit. Get further advice through the dedicated support channel of that module.
BTW, just above the robots tag are somewhat confusing OG tags the conflict with the correct ones from Yoast. I suspect they come from the same plugin. You’ll likely want those gone as well.