Go to www.google.com and type "Java Tutorial" in the search box, press enter. Now you'll see lotsa links, just click on the first one you like and get going..
I'm sure you understand no one can type something here in this thread that will teach you java..
Or go to your locl library and see if there are any quick-start guides for Java. However, choose wisely. Some programming books will teach you bad programming practice right off the bat just so you can get a program running quickly.