K-Mean clustering determining the optimal number of clusters.

I need to know how to calculate the Within-Cluster-Sum of Squared Errors (WSS) for different values of k, do we have any samples for this to use it for Elbow method.

Or do you have any other method samples to find optimal number of clusters in K-Mean Silhouette Method or Gap analysis.

Please let me know i want to use it for my usescase to find optimal number of clusters.