TLS certificate for Rancher

[Dodoooh]

I am new to the K3S world, I created it with the awesome ansible script.

Now I have installed the cert-manager with traefik as well as Rancher.
https://docs.technotim.live/posts/kube-traefik-cert-manager-le
https://docs.technotim.live/posts/rancher-ha-install

But now I have the question, how can I give rancher a let's encrypt tls certificate? With the example for NGNIX it worked fine, but rancher is installed differently, so I don't really understand this.

Thanks a lot