Hey, there.
Dallas here from the Social Care team at Shopify.
Great question! Although I am not the best person to ask for coding information, I did come up with an option that may work for you. Considering you aren't super comfortable with coding like you said, this may work better for you.
A lot of themes have a feature to add a quantity selector to their product page. If my assumption is correct your product page doesn't have a quantity selector so you are wanting to add a selector to your cart page instead? Am I right? To solve that problem you can go to Online Store > Themes > Customize Theme in your Store Admin. From there you can click on a product page. On the right-hand side, you will see a panel with some page features. If you click on button that says Product Pages
you will see a button near the top that says Show Quantity Selector.
Once you save that your customers will be able to select how many of the items they would like to add to their cart.
Alternitavely, when your customers are in the cart page, they will also be able to adjust the number of items that they see in the cart. To make that change they can just click on the quantity button and either type in a new number or use the quantity arrows that show up upon clicking.
I hope this helps to answer your question in making it easier for your customers to add more products to their cart.
If you have any more questions at all please let me know.
Best,
Dallas
