Family

Hello Haqmal thank you for your question. I will try to answer and guide you through the process and requirements for family reunification.
If you have a legal residence permit in Germany you can bring you immediate family (wife and children under 18) to Germany if you full-fill certain requirements. If you only have a tourist visa then you cannot bring you family to Germany.
One of the main requirements is to show that you earn enough money. you have to earn enough so that you are not entitled to receive any money from the Job Center or the Social Welfare Office - regardless of whether you actually get money from Job-center or the Social Welfare Office. The amount of money depends on the size of you family.
You also have to proof that you have enough space for your family. In principle, you need 12 square meters per person aged 6 and over. You can read more about the other requirements here: https://handbookgermany.de/en/family-reunification-for-immigrants (Also available in Farsi/Dari)
Your family must apply for family reunification in person at the German diplomatic mission (embassy or consulate-general) in their home country or in the country in which they are staying. For Afghanistan please book an appointment though the German embassy website in Kabul. However, you will need to go to the German embassy in Tehran or Islamabad. To do so, your family must make an appointment and bring all the papers with them to the appointment.
The papers include:
1) The confirmation email from the embassy about the appointment
2) Visa applications for all family members
3) An extract from the family register (if available in your country)
4) Birth certificates of all family members
5) Your marriage certificate
6) A copy of your residence permit in Germany

These documents may have to be verified by the German embassy - which means their authenticity must be checked. Authentication of documents can take place during your appointment at the embassy.
The embassy can also request further documents from you. Therefore, before your appointment, check the website of the embassy at which your family have their appointment.

You can read more information on Family Reunification for immigrants here: https://handbookgermany.de/en/family-reunification-for-immigrants
If you are a recognized refugee the process is slightly different.
Please read more information on the process of family reunification for refugees here: https://handbookgermany.de/en/family-reunification

I hope your family can soon reunite with you in Germany.
Best wishes