Installing the interpreter
Python development starts with an interpreter that can execute your source files. Install a supported Python 3 version for your operating system and verify it from a terminal. On some systems the command is python; on others it is python3.
Verify the development environment
Check both the Python version and pip. This helps catch a common beginner problem where an editor, terminal and package manager are using different Python installations.
Create a first project
Keep each application in its own directory. For real projects, create a virtual environment before installing third-party packages. This prevents unrelated projects from sharing package versions accidentally.
Practice: create hello.py, run it from the terminal, create a .venv, activate it and verify the interpreter being used inside the environment.