Hello there, @wendyharrisgloba.
Thank you for posting here in the Community. I can share a solution to help you put all your products in QuickBooks Online (QBO).
When importing Products & Services into QuickBooks Online, the originals will stay and combine with the new additions. However, there is an option to Overwrite all values for each product or service you import with an identical name. Doing this will merge any imported Product or Service with the same name as an existing one.
Here's how you can achieve this:
- From QuickBooks Online, click the Gear icon (⚙) > Import Data.
- Select Products and Services. Click Browse and find the file containing your items.
- Follow the on-screen instructions to map and upload your data. From the list of Products and Services to be imported, check the box at the bottom if you'd like to Overwrite all values for each product or service that you import with the identical name.
- Once finished, click Import.

This information is also available from our guide on importing products and services for your convenience. Using these steps, you can avoid getting duplicates while importing additional items.
If you need a reference, you can check out this article about importing data: Common questions about importing data to QuickBooks Online.
Don't hesitate to let me know if I can be of additional assistance while importing your products or if you have any follow-up questions in mind. I'm always here to keep helping. Have a good one!