Regarding to how to install matplotlib can refer to this website: https://matplotlib.org/3.2.1/users/installing.html You can choose to install via pip or from tar.gz following the instruction in the website If you really have no idea on what are these, simply check this: https://youtu.be/Iq9f2bQJOPg
For me, I install via pip, using:
Press 'window key + r'
Type 'cmd' and click ok
In the comand prompt, type: 'pip install matplotlib'
Regarding to how to install numpy can refer to this youtube video: https://youtu.be/YWn8Wj69Dm4
Some fatal issue is that you don't have the pip in your computer, in this case, check your installation and made sure you checked the add Python 3.x to PATH (https://datatofish.com/add-python-to-windows-path/)