I recommend you go through several tutorials.
Here are a few to get started.
k means clustering in r - Google Search
By all means, come back to the community for specific support, when you try something and get stuck, then you can tell us what you tried and how you got stuck, we are less inclined to do your work for you, but happy to assist you when you need assistance. As you are asking for a complete lesson, the forum is not the best source, I advise you to go look for lessons.