Hello,
Thank you very much for choosing our theme and for contacting us.
1. You need to create the translation for the parent theme.
Here is a video tutorial that should help you translate your website texts with a Loco Translate plugin https://www.youtube.com/watch?v=D3NsDdMzsls&list=PLMw6W4rAaOgKKv0oexGHzpWBg1imvrval&index=3
Please check the video tutorial to see how to save the translation file correctly. You can remove the plugin and translations would remain. Also, translations would remain after each theme update.
In order to translate the Woocommerce strings, you need to create a separate translation in Loco > Plugins > Woocommerce in the same way as shown in the video.
2. It is not possible to set the page title for the product page, unfortunately.
If you have any questions please feel free to contact us.
Best Regards