How to downgrade from Ionic 4 to 3.20

Im having troubles understanding version 4 because I dont have tutorials yet to base on and want to revert back to 3. Currently im back to ionic 3.20. Started a blank project to test it out. When I serve it runs okay, but when I ‘npm install’ it does this.

is this okay? or should I downgrade my angular as well? npm global packages here:

Hi @renasance21
If your project is running and working properly then you don’t need to downgrade your angular CLI.