Cannot follow the lesson - error message

I am getting this error, please help!

The default interactive shell is now zsh.
To update your account to use zsh, please run chsh -s /bin/zsh.
For more details, please visit https://support.apple.com/kb/HT208050.
Iness-MBP:Code_with_Mosh_Python ianchondo$ source /Users/ianchondo/opt/miniconda3/bin/activate
(base) Iness-MBP:Code_with_Mosh_Python ianchondo$ conda activate base
(base) Iness-MBP:Code_with_Mosh_Python ianchondo$ $python3 app.py
bash: app.py: command not found
(base) Iness-MBP:Code_with_Mosh_Python ianchondo$ chsh -s /bin/zsh
Changing shell for ianchondo.
Password for ianchondo:
chsh: Credentials could not be verified, username or password is invalid. Credentials could not be verified, username or password is invalid.
(base) Iness-MBP:Code_with_Mosh_Python ianchondo$

The command is python3, not $python3.

I didn’t add the $, it is embedded in my terminal…

When I type python3 I get the expected message

But I cannot follow the lesson since I continue to get the error message posted above

I have no idea where all the other messages come from but here

you added a superfluous $ before python3 telling bash to expand an environment variable named python3 and since this does not exists the resulting command is “ app.py” which leads to the error message “bash: app.py: command not found”.

?
What do you get if you type “python3 app.py”?

I am not sure how to answer since I am unable to post a picture,

I have the expected >>> in Code

I know you think I added a superfluous $, I didn’t, it is already in my terminal

I do notice that my app.py is all blue, not blue and yellow as the example

In the terminal? or, in Code?