The following URL is the cheat sheet for calculating the numbers of ip address from a CIDR range.
NodeJS should not be installed using sudo / root. The following link has the details for correct nodejs installation
Here is a quick start up article to unit test node.js application using frameworks like Mocha, Chai, Sinon.
The following blog post can be referred for CI/CD setup using Minikube, Helm, JenkinsX