Steps Required: Istio upgrade from 1.3.0 to 1.4.0

Hi,
We need to upgrade istio from 1.3.0 to 1.4.0

We don’t have Istio CNI. I just need to upgrade the control plane and the side-car proxies. Helm charts for version 1.3.0 was deployed with kubectl apply

I’m looking at this doc -

Looks like the documentation is incomplete. Can someone be able to help with the commands ?

Appreciate your help !

Thanks
Aravind.

Any help on this guys ?