Hello,
1) Theme Options > WooCommerce > Single product builder > edit width of sections.
2) Theme Options > WooCommerce > Single product builder > delete elements from sections.
3) Theme Options > WooCommerce > Single product builder > move elements depends on your needs.
“Related Products” text can be changed using translation files. Install and activate Loco Translate plugin > create English translation for XStore theme, change the text. Once it works on the frontend, you can disable the Loco plugin.
Regards