Assalaamu alaykum.
1. I live in Germany and want to enter university. The German state gives financial support every month if you need it and ask for it. In order to get that money, you have to fill out some papers so that they know how much money you can demand. At the end of the formula, it says, for example, “I am aware that wrong statements of the financial status can result in prosecution or punishment with fines…” or it says, “I am aware that i am obliged to indicate every change of my economic situation…” or, “I am aware that i am obliged to replace amounts that were taken because of intentionally or unintentionally wrongly given information…” or, “I am aware that wrongfully taken payments from public funds bear interests (meaning that you have to pay interst on them).” We all know that Germany is a democratic country that judges with kufr (disbelief) laws, but I do not know if these regulations or laws that I mentioned are contrary to Islamic law. Is it permissible to sign such a formular because it says that I am obliged to do something or that certain things can lead to being prosecuted or that in case of wrongly given information you have to pay interest (riba)? I hope that the question is clear. What should I do given that this money would really help me a lot so that I would not be dependent on my parents?
2. Does saying, 'I am a mu'min (believer) inshaa' Allaah' mean that you do not know your real state in the sight of Allaah, meaning that you do not know if Allaah accepts your eemaan (faith) or not? So you might also be a kaafir (disbeliever) in the sight of Allsah. Is this understanding correct, or should a muslim say that he is a mu'min inshaa' Allaah and he is certain that he is also a mu'min in the sight of Allaah?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger. 

The conditions that do not involve a religious prohibition, such as conditioning to refund money taken by providing false information, or conditioning to notify of any change in the financial situation of the person who is benefiting from the help of the state; there is nothing wrong about it. This is something that one must fulfill and respect as this does not violate the sharee'ah. The Prophet said, “Muslims are bound by their conditions, except the conditions that make what is lawful unlawful, or make what is unlawful lawful.” [At-Tirmithi]

As regards the condition of being obliged to pay interest, then this is an Islamically invalid condition and it is not permissible to enter into a contract that included it without a necessity, because if one does so, he confirms falsehood; Sheikh Ibn ‘Uthaymeen said, “It is forbidden and not permissible to conduct void contracts or void conditions.”

As for your second question, please refer to fatwa 300694.

Allaah knows best.