If you have a program that you would like to run automatically after turning on the Raspberry Pi, you have to follow these steps:

1. Type this command into the terminal: sudo crontab -e.
2. At the bottom of the file that has opened, write: @reboot sudo python3 /home/pi/Desktop/test.py.
3. If later on you want to stop the program, commend this line. Remember that if you run this program in the background and then use it from the code editor, some errors may occur.