Hi vismaymehta,
Welcome to the Community. It's essential to correctly record your bills and bill payments to keep your books up to date. QuickBooks Online is a great program that gives you the ability to easily track your sales and expenses. I'd be glad to point you in right direction to get the support you need regarding API.
I encourage you to reach out to our Intuit Development Support for their expertise, to ensure you're able to accomplish your goal.
Let me know if you have any questions, I'll be happy to help