Steps to move from paypal to Stripe?
You would need to reach out to Paypal and Stripe directly to ask them about how to initiate the process of transferring your recurring giving.  I would suggest inventorying your existing recurring records in Paypal first, to see how complex the data is; in a recent transition to Stripe, we encountered some challenges with constituents who had multiple payment profiles.  The more clarification you can get from Stripe about what will be required, I think the more smoothly this will go for you.  (Typically the processors would need to transfer the payment details directly.)

Hope this helps,
Lesley