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In general, rules and regulations applying for a marriage in your country of origin will be important for your marriage in Germany also. The German authorities want to be sure, that your marriage will be recognised in your country of origin as well.
One essential document will be the so-called "certificate of no impediment", which both of you will need to provide.
The first step would be to contact your local "Standesamt" in order to register the marriage. They will provide you any further information, i.e. which additional documents they require in your individual case.
I hope my answer was useful for you.
All the best for you and the marriage!