Hi there,
Your Chart of Accounts is automatically generated when you set up your QuickBooks Online company file. Based on the type of business you select, QuickBooks knows what kind of accounts to add, and the categories you may need. I'd be happy to explain how to review the accounts in QuickBooks Online, as well as how to add new ones as needed.
If you click on the Accounting tab on the left menu, then click Chart of Accounts, you'll be directed to your accounts list. Here's where you should look for a Corporate Tax Liability account. If you don't see it there, you can add it by clicking New.
Here's an article that will provide more in-depth instructions on how to add a new account to your Chart of Accounts: Add to or edit the Chart of Accounts.
This article should give you all the information you need, but if you have any further questions, let me know.
Have a great day!