I'd be glad to suggest steps that can fix it, hirahumayun17.
It's possible that the Inventory Tracking feature is not turned on. This is the reason why the Item details section is not showing up when creating bills.
Let me share these steps on how to turn it on:
- Go to the Gear icon and select Account and settings.
- Proceed to the Sales tab, then click Products and services.
- Look for Track quantity and price rate and Track inventory on hand. Then, turn them on by dragging the slide bar to the right.
- Click Save and choose Done.
Once done, go back to the Bill section and check if you can already see the Item details section.
Let me also share these articles for additional reference:
Don't hesitate to reply to me and let me know if that lets you see the missing section. You can also ask follow-up questions if you still need more help from us.