How to generate expense by category like travel expense, rent expense, telephone expense?

Hello,

Welcome to QuickBooks Community! 

In order to add a new expense category to the Chart of Accounts, please follow these steps:

1. Click Accounting on the left panel.
2. Click the New button at the top right.
3. Select the Category Type (Expenses or Other Expenses).
4. Select the Detail Type (see the description below to help you select the right type).
5. Enter the Name.
6. The Description is optional.
7. Click Save and Close.

I hope this helps.