how do I delete items in Product/Services?

In QuickBooks Online, you cannot directly delete a product or service. Instead, you can make them inactive so that they no longer appear in your lists, reports, or transactions. Here are the steps to make a product or service inactive:

1. Navigate to the Sales tab.
2. Select the Products & services section.
3. Locate the item you want to make inactive.
4. Click the dropdown arrow next to the Edit button and select Make inactive.
5. A prompt will appear; click Make inactive to confirm.

Once an item is made inactive, it will no longer be available for use in new transactions or reports. 

For more detailed information, you can visit this article: Make an account inactive on your chart of accounts in QuickBooks Online.

I'm also including this article for future reference to learn how to change the item type or make some changes to your inventory items: Change product and service item types in QuickBooks Online.

Feel free to comment below if you have any more questions about QuickBooks Online.