I assume that you set selenium properly.
1 - Go to your eclipse.
2 - Go to menu File ->New -> Java project. Give project name like "test" or anything you like.
3 - Click on Next.
4 - Select tab "Libraries" , Select option "Add external JARs"
5 - Add following 3 JARs :
A- selenium-java-2.43.1
B- selenium-java-2.43.1-srcs
C- selenium-server-standalone-2.39.0
6 - click on Finish. [Your project creation steps completed here]
7 - Now , Do right click on your project folder and select new->class
8 - Give class name and tick option "public static void main(String[] args]"and click on finish.
Please add below code before your classname in code :
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
After above step , run following sample selenium web driver code to open site :
WebDriver driver = new FirefoxDriver();
driver.get("https://www.google.com");
Hope above will help you better.
Other selenium helpful tutorial : Selenium Tutorial