Hello,
1- As you know the Products are handled by WooCommerce and the Theme doesn’t influence it. So, if you want to hide the Single Product page then we would suggest you to contact the WooCommerce Support in this regard. They can provide you a sort of Code Snippet or a way through which you can make the Single Product page inaccessible. This is not a common practice, so it’s hard to find an alternative solution for that other than contacting the WooCommerce Support. Hope you can understand this !
2- Regarding the Watermark concern, sorry to say but there isn’t specifically a Theme end concern and there is no option in Theme Settings available for that. It requires Customization and this is beyond our limitations and support policy scope. Hope you can understand our limitations.
Best Regards