Dear Sir Good Evening I am new employee of Simbus and not able to handle to raise the debit note in Quik book.. please help

Let me be the first to welcome you to the Community, userrajakumar-r.

If you're trying to create a printable credit note in QuickBooks Online (QBO), right now it's unavailable. You can use the Journal entry feature instead if it is for customer expenses incurred on their behalf. 

To create a journal entry, here's how:

1. In the left menu, click the + New button. 
2. Choose Journal entry. 
3. On the first line, debit the Accounts Receivable (select the customer's name) and enter the amount.
4. On the second line, credit the Expense account and enter the amount.
5. Select Save and close.

Once the customer makes a payment, create a deposit. 

However, if you're trying to create a debit note for a supplier for returning the items or for some other reason, then, use the Supplier credit option. 

Here's what you'll need to do:

1. In the left menu, click the + New button. 
2. Choose Supplier credit. 
3. Pick the supplier's name.
4. Select the appropriate account to be credited in the Account details section.
5. Enter the other necessary information.
6. Select Save and close.

If the supplier pays back, enter a deposit. 

For more details, take a look at this article: How to create a debit note in QuickBooks.

If you have additional concerns or any questions about debit note, let me know by adding a comment. I'm always here to help. Have a pleasant day ahead!