Help with function

Can someone knows about subscribe function on website?
and payment fuction wherein you can choose 2 option 1st option is via paypal, then 2nd option is via credit card
can someone help plz? using php language

A payment subscription? PayPal can generate them for you in the merchant tools...and if you use something like Stripe, they have documentation readily available to help you create credit card payment subscriptions via their API.