I would like to change the credit card on the system, that I use to pay the monthly fees...how do I do this?

I can absolutely guide you in updating the billing details in your QuickBooks Online company, @Madhunika.

If you're subscribed for QBO through a web browser, make sure to first log in as a primary administrator. Then, you can proceed to add the new payment information by navigating to the Billing & Subscription page. Here's how:

1. Click on the Settings (Gear) icon.
2. Choose Account and Settings under Your Company.
3. Select the Billing & Subscription tab.
4. Hit the Edit (Pencil) icon next to Payment Method.
5. Edit your credit card number and the details.
6. Ensure the Billing Address in the program is the same as the one on your credit card statement.
7. Once done, hit Save.

See this to learn more about handling your subscription: Manage billing, payment, and subscription info in QuickBooks Online.

I'm just a reply away in case you need extra help in managing your account. I'll also answer questions about QuickBooks in particular. Have a great rest of the week!