If you are using a virtual environment, follow the steps below to setup it for the Jupyter Notebook.
$ source <envname>/bin/activate
$ pip3 install ipykernel`
Next, run the following command to create a kernel in order to use our virtual environment in the Jupyter Notebook
$ python3 -m ipykernel install --user --name <envname> --display-name "<envname>"
You should now be able to select the created kernel from the Jupyter menu bar (Kernel/Change kernel, see picture below).
$ jupyter notebook