Thank you for using Apple Support Communities. It seems like you want to download an app but it is still not downloading. You have not mentioned what is happening when you try to download it. One thing you can do is download the app to the computer using iTunes and sync it to the iPhone. I would recommend you read these articles, they explain how to do it.
iTunes for Mac: Sync and organize iOS apps
iTunes for Windows: Sync and organize iOS apps
Take care.