upgrade latest version of node code example

Example 1: how to update node js version

//check node version
>node -v
// let's install a program called n that will let us easily switch 
//between Node versions.
>npm install -g n
//Upgrading to the latest stable version
>n stable 
//Changing to a specific version
>n 10.16.0

Example 2: update nodejs version

npm cache clean -f