The problem seen in the screenshot is that the Python Library cannot be found. So some configuration in your pyinstaller is wrong. Are you sure that python36.dll is in that folder? Check where your python36.dll is located (normally in the same folder where your python installation is located and your python.exe can be found). Maybe you need to add this path to your Windows Path Configuration?
Please check the following two answers to see if your pyinstaller is configured correctly:
The situation should be similar for you with Python 3.6