iPhone change from vertical to horizontal
When I try to buy an app from the Apple Store, it asks for my password. But I cannot make the screen go wide enough to enter the password, because it won't go horizontal.
iPhone 8, iOS 14
Confirm your screen is not zoomed.
Click or tap on the following blue-text link for more about setting and disabling display zoom:
Zoom in on the iPhone screen - Apple Support
I wouldn’t expect the password box to be off the display, if the display isn’t zoomed.