Navigate to Services >Add New in your WordPress admin sidebar. And follow the screenshot for add new service post
Title: Give your post title in title field.
Content: Give your content in content area which goes to your post details body.
Services Category: You can categorized your post by using default or featured.
Banner Background Image: You can upload background image from the option.
Featured Image: This image for service post card.
Custom Posts Custom Link: Here used two types of link. Post Details Page and Custom Link.
the others areas are also for services details.