There are people who have decided to switch over from using a PC to using a Mac. When this happens, you will have to learn the new operating system that you are going to be using. This is going to take a bit of time to learn since it is a new system.
The best advice is to first forget all your old computer habits. You will want to be able to do things the way you are used to and for many this may cause frustration. Just relax and realize that things are done differently. Be open minded about the process to not be as frustrated.
Go to Apple's site and look for the "Grand Tour". There are a series of pages here that will give you an overview of the new operating system that you are going to be using. This site will show you with detailed pictures and labels about what each part of the interface is so you can understand everything.
Read popular forums on switching over to a Mac. Many times there will be some very common newbie questions that will be answered over and over. This is a good resource to get the basics of what you need to know and avoid common issues.
Watch Youtube. There are many tutorials and how to videos that will give you information on the basics. Look for "mac tips" and you will have hundreds of videos that you can watch to get more information.
Get some manuals that are available for new users. There are many third party books that are designed to step you through the process so that you can learn what you need to know.
The best way that you can learn is to simply sit down with the system and start learning it on your own. Go to a store, friend's house, or get your own computer to start the process.