Open the Settings app
Tap Display & Brightness
Tap Display Zoom
Select Larger Text if available
Tap Set
Go back to Settings
Tap Accessibility
Tap Display & Text Size
Turn on Larger Text
Drag the text size slider to the right
Go to Settings
Tap Accessibility
Tap Zoom
Turn on Zoom
Use three fingers to zoom in on the screen
On the Lock Screen, press and hold the wallpaper
Tap Customize
Tap the time
Choose a larger font style if available
Change the Lock Screen font weight if available
Use a higher-contrast wallpaper to make the time easier to see
Turn off Low Power Mode if it affects display behavior
Restart the iPhone if changes do not appear immediately