The tuning of the integration of wordpress and robokassa

This page on the website with order forms. The site is up on worpress and hosted nic.ru. The company sells business trips (i.e. not a physical product, and service)
What to do: you Need to redo the application form on the payment form and configure integration with robokassa service.
Optional – to customize the normal display of the page on mobile devices.
The cost and time estimated.