We have an existing QB and the existing Chart of accounts are not friendly to hotel business.Do we block the existing one and create new ones altogether?

You're unable to block the existing or default accounts in your Chart of Accounts (COA). However, you can create new ones instead, @frednjogu4-gmail. Let me provide further details about this.

The Chart of Accounts (COA) is used to organise all your company’s accounts and balances. By the time you set up your business in QuickBooks Online (QBO), it automatically creates your COA based on the industry and type of company you choose.

You can add your accounts, but since QBO has its default ones, I'd recommend consulting your accountant for it. For the step-by-step guide, here's how:

1. Go to the Gear icon.
2. Select Chart of Accounts.
3. Click New.
4. In the Account Type drop-down, choose an account type.
5. In the Detail Type field, select the best type that fits for the transactions you want to track.
6. Enter its name, then add a description.
7. If you’re adding a sub-account, select Is sub-account and then enter the parent account. 
8. Choose when you want to start tracking your finances and all other necessary details.
9. Select Save and Close.

In case you're still in the process of setting up your company and you wanted to add more accounts, you'll have the option to import them in QuickBooks. Kindly refer to this article for the complete details: Move your chart of accounts to QuickBooks Online. 

After completing your COA in QuickBooks, you can connect your bank and credit card to automatically bring in your transactions. All you have to do is review, categorise, and approve them. For the detailed steps, you can check out this article: Connect bank and credit card accounts to QuickBooks Online.

Please let me know if you have other concerns. I'm just around to help. Take care always.