If you want to access the server directly via ssh, the first step is to find out the IP address of the nodes:
Copy the IP address of the node, shown in the EXTERNAL-IP column and ssh into it using yout ssh key:
The command-line utility kubectl offers pratical ways to access your nodes's shell.
List your nodes:
Now, copy the name of the node you want to connect to and run:
In the command above, busybox is used since it's a lightweight container image loaded with basic utilities you expect to find in a Linux environment, but you can use any container image you want, like ubuntu for a more complete environment or nicolaka/netshoot for specialized networking debug tools.
For more information, you can refer to the official Kubernetes documentation.