More information: https://www.macobserver.com/tips/quic...
Open a webpage in Safari
Take a screenshot by pressing the side button and volume up button together
Tap on the image in the bottom left corner on your screen
Tap the 'Full Page' tab (you can see it's the whole page by holding down and scrolling on the right-hand side of your screen.)
Tap 'Done'
Tap Save PDF to Files,
Pick the location where you want the file to be stored, and tap 'Save'