When you learn a foreign language, often you have questions because you don't understand something completely yet. You can ask these questions here.
You can also write German texts here ("notebook entries"), and have a native speaker correct them, so you can learn from your mistakes.
To learn German, you need to learn about cases, word order and grammar in general. You need to learn vocabulary and pronounciation. There are many internet sites you can use for this; google a bit.