100 Doors Parallel Worlds Level 45 Walkthrough is shown below with screenshots. The answer is explained in detail in the text. Look at the screenshots for more help. If you only want to look at part of the guide and not cheat, just look at part of the solution. This will help you go to the next door.
1. Pick up the pickaxe and put it down into the bottom right corner of the cement walls.
2. Shake your phone/device to drop the tip of a shovel. Pick up the pickaxe handle and use it on the shovel tip to make a shovel.
3. Dig with the shovel in the dirt on the bottom left corner closest to you to get a key.