In VS Code, open your terminal by pressing Ctrl+(backtick) or going to Terminal > New Terminal. Make sure you're in the folder where you savedhello.py`.
Type python hello.py and press Enter. You should see "Hello World" appear in the terminal. That's it. You just ran your first Python program. If you see "Hello World", congratulations.
If you see an error, check three things: Is the file saved? Are you in the right folder? Did you spell the filename correctly? These account for % of "my code won't run" problems.