Hello,
01. 02. Actually, with some of the Demos there are certain Custom Layouts enabled for the Single Product and Archive pages which is why your made changes under the Theme Settings aren’t taking effect on that.
Navigate to Layouts > Edit single product layout and add the sold counter widget to show this.
Further, you can read more about the Layout Builder here: https://xtemos.com/docs-topic/woodmart-woocommerce-layout-builder/
03. I have checked your site and it is showing fine on mobile.
See Screenshot for clarification: https://ibb.co/7dGvmgrJ
04. Yes, your Track Your Order page is working correctly. You do not need to install any additional plugin for this feature.
WooCommerce provides the order tracking functionality by default, and the shortcode you added is the correct way to display the tracking form on a custom page.
As long as customers enter a valid Order ID and Billing Email, the order details will be shown correctly.
Best Regards,