Hello,
Thank you very much for choosing our theme and for contacting us.
There are two options to add an additional tab to the Product page: Global – in the Theme Settings > Product page > Tabs – the content would be shown on all the products, like shipping and delivery in our demo; Another one is the individual Additional tab for products that are added in the product page – https://xtemos.com/docs/woodmart/product-page-options/#local_settings
When you add attributes to the products, there is the option to show the attribute on the product page, enable it and the tab with all the attributes would appear.
Best Regards