You can bring up a undo/redo/copy/paste toolbar by tapping one time with three fingers.
How to Bring up undo/redo/copy/paste toolbar
NEXT TIP
Undo or redo with a three-finger swipe
Swipe left with three fingers to undo and right to redo without using the on-screen menu.
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10 iPhone Gestures and Shortcuts You Should Know
Essential iPhone shortcuts including back button navigation, three-finger gestures, cursor control, and text replacement