Click on an operation. When it asks you for the first number, type in your first number. When it asks you for a second number, type in your second number. It'll then ask to confirm the numbers. Type a to get the answer, and type b to choose again. Finally, you'll see the number displayed.
Display time is (in seconds) the time that the program will show your numbers and results. Press the up arrow to increase it by 1 second and the down arrow to decrease it by 1 second. This can do decimals and negatives too (sorry, no fractions)! Hope it's useful!
