Picture Field Datatype

Hello everyone, when working with picture fields, which type of field should be usedB in the workflow? Suppose I have this picture in module “A”, but now using an workflow, I want to copy this image to another module “B”.
I have noticed, there is a attached field in the datatype, but that field results in an error. So which field type or technique should be used in this scenario. Any help would be much appreciated here.