Help connecting to payment gateway using custom code

[ramdesh]

Hello,
I need to simply pass the total price to the VirtueMart payment gateway for Authorize.net and get credit card details from there. I will be storing the total price using custom code in a database table. All I need to do is pass this price along to the payment option and initialize the payment procedure using VirtueMart from there.

Can anyone help me with this?

Thanks in advance!