If you are going to work on an existing project, there are a number of different ways you can import it into Eclipse, depending on how you have obtained the project's source code. To open the Import wizard, navigate to File | Import. Let's go through the options under the General category:
Archive file: Select this option if the project you are working on already exists in your workspace, and you just want to import an archive file containing new resources to it. The Import wizard will list all the resources inside the archive file so that you can select the ones you wish to import. To select to which project the resources will be imported click on the Browse button. You can also select in which folder the resources are to be included. Click on Finish when you are done. The imported resources will be decompressed and copied into the project's folder.
Existing Projects into Workspace: If you want to import a new project, select this option from the Import wizard. If...