I have a cisco 1900 router connected to ISP with Static IP address and therefore the router has been configured to act as DHCP to the two switches behind it and everyone hosts connected to the switches are browsing.

Now, I would like the ASA to see with ISP, while the router are going to be behind it and therefore the switches are going to be behind the router. 

What basic config am I able to do on the ASA to realize this? Though, we are getting which CCNA Traning In Pune to introduce a centralized server such some members of the LAN are going to be ready to access it. Also, do I want to vary any config on the router again?