If you're not already in the Shopify ecosystem, I'd look at Stripe Subscriptions with Checkout which requires a small amount of development that lives in something like a lambda or netlify function. - https://stripe.com/docs/billing/subscriptions/checkout - https://www.netlify.com/blog/2020/07/13/manage-subscriptions...

If you want something out of the box, there are tools like Memberful, Gumroad, etc that take quite a vig on top of the payment processing.