Hello,
The Related products come from our theme, you can enable/disable it in Theme Settings-> Single product. But options that you want to enable in the “Product Data” panel come from WooCommerce and are called Cross-sells and Up-sells products.
Cross-sells are products that you promote in the cart, so they don’t appear on the product page.
https://prnt.sc/1znf5pd
Up-sells are products that you recommend instead of the currently viewed product. This option should work correctly on the product page, please check again.
https://prnt.sc/1znflpf
Here is the documentation providing more detailed instructions about Up-Sells and Cross-Sells products:
https://docs.woocommerce.com/document/related-products-up-sells-and-cross-sells/#prettyPhoto
Kind Regards