If you have just arrived in Germany, you will not receive a space in an Integration Course (Integrationskurs) immediately.
In the meantime, many other opportunities for learning German are available. There are, for example, volunteers who teach German: either on an individual basis or in small groups. This is a great way to gain basic knowledge of the language.
As soon as you have been granted the right to stay in Germany, you can and must attend an Integration Course. The course consists of two parts: 600 hours of German language learning (Deutschunterricht) and 100 hours of introduction into German government and society (Orientierung über Staat und Gesellschaft).
The following link provides you with a good overview of the course requirements. A list of volunteer courses is also included.