Here you can find how to work with k-means cluster analysis.
Learning Vector Quantization using R
Here you will learn approaches to split your data into subsets - train and test for your modeling.
Examples of Neural Network classification using Neuralnet R package.
Unsupervised method for dimentionality reduction - Uniform Manifold Approximation and Projection (UMAP).
Here you can find how to work with hierarchical cluster analysis, how choose number of cluseter and how to choose the best model.