Upgrade rancher-2.6.2 rke cluster to newer versions

Hi Team,

I want to upgrade rancher cluster which setup on-prem 3 nodes. I dont have the cluster.yml file with me. I have .rkestate file only. I have multiple k8s clusters in rancher, I have to upgrade them as well.
Do you have any suggested steps to generate cluster.yml to upgrade the rancher RKE cluster to newer version. Or Please provide me the steps to upgrade the cluster.
OS: rhel 7.9

Thank you in advance.

Showing provider as RKE1 and kubernetes version as 1.20.11.


you maybe want to have a look on: Retrieve kubeconfig from RKE or Rancher 2 custom cluster controlplane node for RKE v0.2.x+ and Rancher v2.2.x+ ยท GitHub

and then go along: Upgrades | RKE1

Additionally also: Lost rancher-cluster.yml for RKE - #2 by mattmattox can be helpful.