Two step payment process

Hi,

I am having difficulty in achieving a scenario where I want to validate a credit card without any actual money deducted from bank account in first step and then after successful validation actual money should be deducted in the second step.

What I tried so far is, selecting a transaction type as "authorize" for validating a card and then do a transaction of type "purchase", problem here is they both are deducting money,

In terminal it shows, pre-authorization and tagged void as two types of transactions.

How can I achieve this?