importing matplotlib in jupyter notebook

[snippsat]

I clicked on the miniconda command activate in my Windows 10 program list

You should probably not click on anything,most learn to to all from command line.
Eg use Anaconda Prompt,i use cmder(as it's much better that cmd/powershell).

When you have py-de in envs dos it means that this is virtual environment.
Then most activate py-de to use it.

miniconda3\envs\py-de\...

Quick demo and i use Anaconda prompt for this demo,and new_env as i made it before in link posted.

# See (base) environment is active 
(base) PS C:\Users\Tom> conda activate new_env

# new_env is activated,for you py-de
(new_env) PS C:\Users\Tom>

# Test python 
(new_env) PS C:\Users\Tom> python -V
Python 3.9.1

# Test pip see that it point to new_env folder.
(new_env) PS C:\Users\Tom> pip -V
pip 20.3.3 from C:\Anaconda3\envs\new_env\lib\site-packages\pip (python 3.9)

# Test conda
(new_env) PS C:\Users\Tom> conda -V
conda 4.9.2