I appreciate you sharing this matter in the Community, Ana. To experience the new interface in QuickBooks Online, click the Gear icon at the top right corner, scroll down, and you will see the Switch option. 

You can refer to these screenshots:

Selecting this option will seamlessly transition your account to the new interface, allowing you to benefit from the latest features, improved navigation, and an enhanced user experience designed to make managing your finances more efficient. If you need any guidance while exploring the new layout or have questions about specific features, please don’t hesitate to reach out. We're here to assist you every step of the way!