To be able to run Tensorflow you have to have installed Python 3.6.x + 64 bits, make sure it's 64 bits because a 32 bits version doesn't work.
To run everything run the following command:
pip install keras-rl h5py gym tensorflow numpy matplotlib graphviz pydot pydot-ng
Download graphviz from and install it at: "C:/Program Files (x86)/Graphviz2.38/bin/":
https://graphviz.gitlab.io/_pages/Download/Download_windows.html