VSCode running Python 2 instead of 3

I am using Python with VSCode, and if I use Cmd+Shift+P and type Run Code, it runs the code with Python2 even though I have specified it to use Python3. I have read this tutorial: How to force VSCode to use Python 3 instead of Python 2? but I do not understand how to change it. (and I can't comment because I don't have enough reputation yay) Could anyone help? Thanks!

Maybe it could be related to the fact that the mini terminal at the bottom runs "python -u " instead of "python3 -u "? Does anyone know how to change that?

Please note the command Run Code is not provided by the Python Extension for VS Code, instead it is provided by the extension Code Runner. They are two separate extensions. You'll need to configure that extension to point to the Python Interpter you have chosen. I.e. as per their docs on the home page you have to update the settings:

{
    "code-runner.executorMap": {
        "python": "<fully qualified path>",
    }
}

Or you have another solution, that's to use the command Python: Run Python file in Terminal. This does not rely on the Code Runner extension and is part of the Python Extension hence using the interpreter you have selected.