It's nice to see you here in the Community, @danielasabau.
I'm here to get you pointed in the right direction so you'll be able to link QuickBooks to your application and have it accessed through API.
QuickBooks Online integrates with various third-party applications to help you run your business easier. To help you with integrating your application with the program, I suggest contacting our Intuit Developer. They are the experts when it comes to enabling applications to access the production of QuickBooks Online companies.
You can reach them through this link: Go-Live with your application.
In addition, you may also consider check this article attached in case you have questions concerning QuickBooks and its functions: Getting started with QuickBooks Online.
Know that I'm just a reply away if there's anything else that you need. Thanks for coming, and have a good one!
