to start with :
goto application.properties and set your
STRIPE_PUBLIC_KEY
STRIPE_SECRET_KEY
or inject them athe env variables
run application aas normal spring app.
for api specification visit http://localhost:8080/swagger-ui.html#!/orders45controller/postOrderUsingPOST
for api test , you can use test payment cards from stripe sandbox https://stripe.com/docs/testing#international-cards