Welcome to the Wefugees community and thank you for your question.
Did you apply for "Kindergeld" (child benefits) at "Familienkasse" of Jobcenter? That's 194€ per child per month. Additionally, your wife is entitled to get financial support (ALGII) through Jobcenter. Keep in mind that if you are living together you might be treated as a "Bedarfsgemeinschaft" by Jobcenter. That means your wife's ALGII might get lowered since you are having an income that is used to finance the household.