Below are the commands and their outputs:
root@k8s-master:~# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
cp: cannot stat '/etc/kubernetes/admin.conf': No such file or directory
root@k8s-master:~# kubectl get services -n kube-system
The connection to the server localhost:8080 was refused - did you specify the right host or port?