Commandline is …any interface reading typed commands and responding
What you’re looking for is a unix-like environment, typically that’ll be bash and a quite a large number of other small programs (like touch and mkdir)
There are several environments that come close to this that run on windows. I suggest installing msys2 or wsl, shouldn’t matter which. There’s also git bash, but I’m not sure what exactly it is, it might or might not also do what you want.
If you go with msys2, after following their instructions for installing you can search for python packages with
$ pacman -Ss python
likely the package you are looking for is named one of: python, python2, python3
which would then be installed with:
$ pacman -S python
For wsl I believe it would be:
$ apt update
...wait little bit while it updates its index
$ apt install python3
If not, well, google it.
What’s going on with apt/pacman is that both those systems have curated lists of packages that you can download and install, and those programs are used to download/install/uninstall and other similar tasks
The most important thing for getting what you want is to keep in mind that YOU have to decide what you want to happen, these tools have very few opinions and are there to do as you tell them.
This is contrast to windows which usually only offers a very small amount of buttons where each action makes sense.