Hello, @Amy V,
We are pleased to hear that you have been able to resolve your styling issues.
You can adjust the “Products Per View” for “Related Products” from XStore >> Single Product Builder >> Related Products as per your needs. Please refer to the attached screenshot for further reference: https://postimg.cc/rd4qV23k
And in order to change its style you have to change the style of the complete shop products and it will adapt that style automatically, you can find the setting under XStore >> Theme Options >> WooCommerce >> Shop >> Product Design as per your requirements.
For the upsell products, you can add them by editing the products in your store. This will allow you to show as many upsell products as you would like on the front end. This is the only way to do this. Please refer to the screenshot provided here: https://prnt.sc/23o1wx5
We wish you all the best.
Best Regards,
8Theme’s Team