Angular is constantly updating its versions, every 6 months. There are two ways to make the change: using the Node.js version manager or via command line.

a) Via Command Line:
First, check the Angular version you are using with: ng serve. Then, open the terminal in administrator mode and uninstall the current version: npm uninstall -g @angular/cli.

Now, verify that the cache is correct: npm cache verify. If there’s no error, proceed; otherwise, clear the cache with: npm cache clean --force.

Next, install the desired version (in this case, version 16 which installs the most stable version): npm install -g @angular/cli@16. Verify the installation with: ng version.

b) Via NVM:
Select the version of Node.js to use and install the compatible Angular version with: npm install @angular/cli@12.2.8.

Note: The LTS (Long Term Support) version of Node.js is the stable version and is recommended for most production projects as it receives support and security updates.

You can install a different Angular version for each Node.js version. To see the Angular version: ng v.

Check compatibilities at: https://angular.dev/reference/versions