How to host a FlaskWebApp with a cronjob

Hello Stackoverflow community!

I am generally new to deploying and hosting, and now I reached the point were I need help :D

What I want to archive:

Deploy my Flask Web App to DigitalOcean Have a .py script ( selenium webscraper ) inside that application run every 24h, to update the db inside the application.

My Project overview:

~/ProjectFolder
    | --app.py
    | --scrape_data.py
    | --chromedriver.exe
    | __/.venv
    | __/my_project
        | -- __init__.py
        | -- models.py
        | -- forms.py
        | -- db_connector.py
        | -- database.db
        | __/routes
            | -- allmyroutes
        | __/static
            | -- allmycss/stuff
        | __/templates
            | -- allmyrtemplates

Problems:

Wen I create a droplet and git clone my code into it, and run "pip install -r requirements.txt", I still can't run "python3 app.py" cause I get "x module not installed error". Wen I now type "pip freeze", I can see that said module is installed???

Question: How can I do this? :D Are there other ( better) ways of archiving my goal?

Thank you in advance for help.