Pennsylvania currently only allows the sale of cannabis to registered medical marijuana patients.
Pennsylvania requires patients to be at least 18 years old to shop, unless they're a patient and are accompanied by a parent, guardian or caregiver. Pennsylvania doesn't offer reciprocity so only patients with a valid Pennsylvania medical marijuana card are allowed to shop at the dispensary.
For curbside, there may be other passengers in the vehicle of any age, and they are not required to provide identification. Only the purchaser must provide their valid medical card and ID.
See also:
What information is required to shop in Pennsylvania?