Is it possible to change all products types in bulk from non-inventories to inventories?

I can share some information about updating product types of your non-inventory items, @mahmoudt-elmasha.

The option to update product or item type from non-inventory to an inventory item in bulk is currently unavailable. That would be a great addition to the current features that we have, so I'll take note of it. 

In the meantime, you'll need to update this one by one. Follow the steps below:

1. Go to Gear icon ⚙ and select Products and Services.
2. Find the non-inventory item you want to change.
3. Select Edit in the Action column.
4. Click the Change type link beside Non-inventory and choose Inventory.
5. Choose Save and Close once you're done.

Here's more information about changing non-inventory and service items to any other type or vice versa: Change product and service item types in QuickBooks Online. 

For more information about adding and adjusting your inventory items, refer to these articles: 

• Set up and track your inventory in QuickBooks Online
• Adjust inventory quantity on hand in QuickBooks Online

From here, you can now create an invoice or add a sales receipt in tracking items that you sell.

I'm always here to provide help and answer any questions that you may have about product and service item types. Just let me know by leaving a reply below. Have a great rest of the day!