Hurray for adopting!
On being allergic, make sure you know what aspect of cats your boyfriend is allergic to. Some people are allergic to cat dander, saliva, hair, etc.
Once you have adopted, take your new four legged companion to the vet for an overall check up and to schedule for a HCM scanning.
Sphynxs have very fast metabolism so make sure to buy a good quality food and check for food allergies ( sphynxs are known for stomach issues and sensitivities).
Your new baby will need ear cleanings every few days, baths about once a week, cleaning between toe webbing since a week and face cleanings every day.
Just because they do not have fur, doesn’t mean they are “easier” to take care of. Sphynx require more cleanings and vet checks than a typical DSH feline.
There is a lot but if you have specific questions, feel free to ask :)