We understand that you're having trouble finding the feature to add a header to your app.
Here are the steps you need to follow to add a modern header control in Power Apps:
Add Power Apps Modern Header Control By default, Power Apps canvas apps hide all modern controls. To use them, you must enable the Modern Controls and Themes option from the app’s Settings page.
Go to More commands (…) -> Settings -> Updates -> New -> Enable Modern controls and themes as shown below.
Next, expand the + Insert tab (from the top) -> expand Layout -> Select the Header control as below.
Once added, the Modern Header control will appear on the screen with its default name, Header1. We can rename it to suit your requirements better.
Thank you for your reply! To ensure a great experience for everyone, your content is awaiting approval by our Community Managers. Please check back later.