I understand that you want to select the item in the SKU field, BHollis.

QuickBooks Online will auto-populate the sku number in the SKU field when selecting an item. We're unable to search and select a product in that field. However, we can search and select it in the Product/Service field using an sku number.

Simply enter the sku number and QuickBooks will show you the result. Refer to the screenshot below:

I'd like to share this article about customizing sales forms. This will guide you on how to personalize not just the invoice, but also the estimates and sales receipts.

Comment below if you need more help with your products/items. We're open 24/7 to help you.