Front-end projects run locally

How front-end projects run locally, I want to modify some front-end pages myself, and debug.
I run NPM I, then NPM Run Serve, open the project error, and is white screen

Hi

Try using YARN as instructed in the documentation and README.
Open your browser console to see if there are any errors.

You’ll not be able to use this using only frontend app(s). You’ll need the backend (server) as well.

https://docs.cortezaproject.org/corteza-docs/2021.3/developer-guide/web-applications/index.html