Getting error Argument or block definition required for modules

I have a module in that created all resources like Iam,ec2 etc… My requirement is to call only one tf file in dev environment
Ex: …/…/module/core/iam.tf
while trying these getting error like Error: Argument or block definition required
after these i ahve tried like these
module “iam”{
source = " …/…/module/core/iam.tf"
}
but getting error like these
Error: Failed to read module directory
Error: Failed to read module directory

can you guys tell me how to resolve these