-it is simple if you have python installed on your machine -you need to run Calculator.py in terminal -by typing 'python' for windows and 'python3' for Linux -it will go like this 'python Calculator.py' or 'python3 Calculator.py' -this will give you GUI and fill in the required information -like age, gender, height, and weight -Popup will show your BMI

-if you didn't install python on your machine. -here is the installation guide https://realpython.com/installing-python/ please refer to it.