My husband is Portuguese I have a 3yrs old son for him I don't knew where he his now because we are separated since 2011.I want to obtain my sons passport for him how do I go about it has is not willing to give him

He's the biological father his name is on the birth certificate

Better way u can directly hire the lawyer from portugal. They will do everything, if u want to submit documents from goa they ask for your portugal marriage registration and bi card of your husband for registration of your child nationality. Please findout the travco service goa on net