Prescription "meth" is just that: meth. Methamphetamine is legal in the US and available under prescription (brand name: Desoxyn). It's scheduled just the same as Adderall -- not that scheduling means much; most of it's science-free political posturing.
Adderall/Vyvanse are amphetamines but not methamphetamine.
Adderall/Vyvanse are amphetamines but not methamphetamine.