Hi there, @madhuri-accc.
Welcome to the Community. I can share some information about the products and services in QuickBooks Online.
Currently, a specific field for the product dimension is unavailable. As a workaround, you can add this type of information together with the item name or by using the Description field.
I can see how beneficial this feature to you. We'll continue to improve QuickBooks, and this preference might be available in the future.
As we assess this, I suggest you visit our QuickBooks Blog to stay updated with all the changes in the product.
For additional reference, you can use the following article to learn more about tracking your items in QuickBooks: Set up and track your inventory in QuickBooks Online.
Feel free to hit that Reply button if you have additional questions. Have a great day ahead.