Do I need a subscription or do I have to buy points?

No. Membership is free and does not require either. Using Maya costs points when you unlock work or run tasks; you can earn points (receipts, referrals, activity), spend your starter points, buy ad hoc packs when you want, or use a subscription only if you prefer points arriving monthly and going 10% further.

Buying points does not unlock a service. Groceries, pet food and Maya's other services open as the savings Maya finds you add up.