can we input the exchange rate when key in sales invoice

Yes, Finance237, you can input the exchange rate for transactions in foreign currencies when creating a sales invoice.

In QuickBooks Online (QBO), you have the option to use exchange rates provided by IHS Markit or manually enter your own exchange rates for foreign currency transactions, as long as you have Multi-Currency set up and enabled.

Please note that this feature is available only in QBO Essentials, Plus, and Advanced subscription plans.

To apply your own rates in your sales invoice, here's how:

1. Open or create an invoice.
2. Assign a customer from the Customer dropdown.
3. In the Rate field, enter the exchange rate.
4. Complete the transaction details and click Save.
   
   I've included a screenshot for your reference:

For more detailed information about applying exchange rates in QBO, check out this resource article: Enter and use your own exchange rates.

Please feel free to revisit this thread with any updates or further questions.