After receiving the official acceptance as a refugee, you can go to the Jobcenter to fill out an application for financial support and a social security insurance number (Sozialversicherungsnummer) for the Rentenversicherung.
Inofficial Arabic version of the jobcenter application documents (these inofficial translation can help you understand the official forms, which are to use):
Checklist for the documents you need to bring to the jobcenter in Arabic (inofficial):
Jobcenter application help
You can find additional information in different languages that can help you fill out the German application for the Jobcenter here: