I used metafab's c# SDK. If you elaborate on your problem, I might be able to assist you.
I used Metafab's currency (https://docs.trymetafab.com/reference/createcurrency) for coins.
Here is the sample code -
to get currency in c# - https://github.com/MetaFabInc/metafab-csharp/blob/main/docs/CurrenciesApi.md#get...
to mint currency in c# - https://github.com/MetaFabInc/metafab-csharp/blob/main/docs/CurrenciesApi.md#min...
all the best for ur project.