Warning: May take a while. I suggest using Turbo Mode. Type in either Prime Test, Prime List, or nth Prime. Prime Test: Type in a whole number to see if it's prime. Prime List: Shows a list of prime numbers. Type Yes or No if you want the list to stop. If you said No, then the list will go on forever. Press the stop button to make it stop. If you said Yes, type in whether you want the list to stop at the nth prime or at a certain number (certain number will have all primes below that number). Then, type in the number you to stop at. nth Prime: Type in what number prime you want. You can also just type in a number at the beginning to test if it's prime.
I did not type in all the primes. Scratch generates them every time.