"How do you produce one?"
Translation:Como você produz um?
If the you is referring to one in general can we use se instead of você?
Yup. You as general, we can say "como se produz um?"
can you also use "you = você" if you are talking about the impersonal "you"? Or if your talking about the impersonal "you" in port, you must use "se" before the verb?
Then, the construction would be different: "como você produz um?" (Not very used, though, for impersonal you)
Not really. Its not related to reflexive verbs... just "you" as general, then we use "se" (how do you make orange juice? = como se faz suco de laranja?)