Airpress doesn’t have anything to do with sitemap.xml
It is possible to customize your sitemap.xml file, so you could add an index of Airpress/Airtable records, but that’s not something Airpress does automatically.
What I do for SEO requirements on sites that use Airpress is to modify the page template PHP file to include the exact OG and META tags that I want. If you’re using Yoast this also requires disabling some Yoast features on the Airpress Virtual Post pages to avoid conflicting meta tags.
Airpress is a fairly low-level tool requiring knowledge of PHP and WordPress internals to do anything beyond some basic ‘virtual page’ stuff.