Chocolatey is a package manager sort of like apt-get for windows, or a command-line version of ninite. You can do stuff like:
Usually you have to run choco as an administrator. That means starting the command prompt as an admin. That can get annoying pretty fast, so I recommend installing the sudo package as the next step.
choco install sudo
After this you can install a bunch of other stuff using "sudo choco install xxxx" install, without starting an administrative shell.
A better terminal, and putty
I installed putty manually instead of using chocolatey because that makes it easier to get conemu to cooperate with putty. see also comments here
For scientific python you might want to try Anaconda instead of installing python yourself. That is not in the chocolatey.
Note this python section is from memory and may not be optimal.
If you already have python2, then you might want to remove it first using the control panel.
If PIP is not found, then it is most likely a problem with your path.