If you don’t want to “damage” the food by cutting into it, invest in a kitchen thermometer!
Use a glove so you don’t burn your finger when you touch the steak. When you’re doing the touch test for the first time, make sure you use a kitchen thermometer or cut into the steak to confirm you’re right!
When cooking eggs, not only should they have shrunk, but both the yolk and the white should be firm.
If your hard-boiled eggs have a greenish tint to the yolk, don’t worry! That’s a natural process and the egg should still be safe to eat.