I'm confused about the usage of the cluster external IP address.

Is this an address that can be used for ingress to access pods running on the cluster?

If so should this be the same as the control plane machine IP address (I only have a single control plane)? Or rather should it be an unused IP address on the subnet that the cluster sits? For example, if I have the below setup:

    Master: 192.168.86.50 Worker 1: 192.168.86.101 Worker 2: 192.168.86.102 Worker 3: 192.168.86.103

Should the external IP address of the master be set to 192.168.86.50 or could I set it to 192.168.86.20 for example?

Also I notice the workers also can take an external IP address should these be set to the same external IP address as the master? If not say they were 192.168.86.21 192.168.86.22 and 192.168.86.23 would that mean I could reach any pod (with ingress setup) to access it on 192.168.86.20, 192.168.86.21, 192.168.86.22 and 192.168.86.23?

I've done some reading around it but I'm still struggling to grasp the concept of external IP address.