Can't run python script from terminal but can from PyCharm: ModuleNotFoundError

I have never run python from a terminal before so I don't know what is involved, I have always run my project from PyCharm. My project runs fine from PyCharm. I am running on Linux. My file structure is as follows:

BackTesting - This is my project
BackTestPkg - One of my packages
initpy
Parameters.py
...
MAX1 - My main development
MAX1_Controller.py
MAX1_Main.py
...
TradingPkg - My other package
init.py
PlatformLib.py
...
MAX1_Controller.py calls MAX1_Main.py, and both call modules in both BackTestPkg and TradingPkg packages, which in turn call other modules in these 2 packages.

When I perform the following at the linux terminal:

/data/stuart/Projects/Python/Env/bin/python /data/stuart/Projects/Python/BackTesting/MAX1/MAX1_Controller.py 'EpicConfigs.csv' 'MAX1.param'
I get the following terminal error:

Traceback (most recent call last):
File "/data/stuart/Projects/Python/BackTesting/MAX1/MAX1_Controller.py", line 10, in
import MAX1_Main as main
File "/data/stuart/Projects/Python/BackTesting/MAX1/MAX1_Main.py", line 8, in
import TradingPkg.PlatformLib as pl
ModuleNotFoundError: No module named 'TradingPkg'

I have created a requirements.txt with the following contents, but to no avail.:
attrs~=24.2.0
colorlog~=6.8.2
matplotlib~=3.9.2
mplfinance~=0.12.10b0
munch~=4.0.0
numpy~=2.1.1
pandas~=2.2.2
pillow~=10.4.0
python-dateutil~=2.9.0.post0
pytz~=2024.1
requests~=2.32.3
six~=1.16.0
tenacity~=9.0.0
termcolor~=2.4.0
pip~=24.2
BackTestPkg
TradingPkg

I have never worked with python outside PyCharm so I don't know what I can try. Other posts I looked at looked complicated and overkill for what I am sure is a simple solution. Can anybody point me in the right direction please.

Regards, StuartM