@chingjunehao If you have tried with this commandsudo apt-get install libsm6 libxrender1 libfontconfig1 and pip install opencv-python and still have issues. I recommend setting up the environment as given by Jermey.
From the Github URL or in the jupyter notebook, you will find the environment.yml file at > courses/fastai/environment.yml
Go to bash and execute the below to install all dependencies using these two commands.
conda env create -f ~/downloads/environment.yml
Activate fastai
Now, it should have the dependencies installed and it should work. Exit and re-login to reflect the changes. No need to restart.
It should technically work…try and let me know.