I have found various answers for this in my searching, but unfortunately my knowledge of VBA is extremely basic and I have been unable to decipher the code 
The description of what I have (names have been changed for simplicity):
I have a form (form1) this form has a subform (subform1)
(ingredients form and component ingredients subform).
I want the subform1 to open a new form (form2) and automatically giving the user the correct linked ID to enter a new field (countries of origin).
The unique field between them is (SubComp_in_ingID)
Thank you.
The description of what I have (names have been changed for simplicity):
I have a form (form1) this form has a subform (subform1)
(ingredients form and component ingredients subform).
I want the subform1 to open a new form (form2) and automatically giving the user the correct linked ID to enter a new field (countries of origin).
The unique field between them is (SubComp_in_ingID)
Thank you.