How to display percent battery charge on screen

On iPhone SE (2nd generation), iPhone 8 or earlier, you can see the battery percentage in the status bar. On iPhone X and later, you can see the battery percentage in Control Center. For more info, see:

Show the battery percentage on your iPhone, iPad, or iPod touch - Apple Support

That information cannot be displayed on iPhones with Face ID. You need to swipe down from the upper right/control center to view the percentage.

~Lyssa