Visual Studio Code compiles with npm, node.js but does not show GUI interaction on localhost:42000 on Ubuntu 19.04

I just successfully installed npm 6.12, Node.js version 12.13 on my Ubuntu 19.04. I also successfully compiled a project using Visual Studio Code. It is my first time using VS and I have been trying to build this project with partial success and I don't understand why, despite the project compile successfully, it does not build.

Below the organization of the project tree:

This is the outcome of the terminal after a launch npm start where I successfully compile but not build:

Finally I can confirm that this is partially working because the localhost:4200 is actually working as is possible to see from the print screen below:

What I tried so far

I tried many different options from launching npm in any possible way from the terminal line embedded in VS, but also using Linux command line.

I went through the entire project and installed all missing libraries such as: scipy, matplotlib and pandas and numpy but still nothing on the localhost side.

In addition I have tried to start and stop several times npm but no luck.

The Problem

I should be able to interact with a graphical user interface but what I see is only the localhost:4200 page without any interaction and only red-ish colored.

What am I doing wrong or missing? Thanks for pointing in the right direction.