I have a 2 year old son who can recognize and say each & every car that is on the road, he can also say 1-20, complete A-Z, he has an amazing memory for instance we went to this place few weeks ago for 2 minutes to order cake and when we went to that shopping center again but on a different side he asked if we are here to order cake.

I would really appreciate if someone can help me on how to develop his skills?

Thank you,

Teach him to start reading as early as you can. See how well he picks it up. Buy him educational toys. You can buy some really awesome ones at the Discovery Channel store. Educational Toys | Remote Control Toys | Discovery Online Toy Store
Also, here is a Google link full of great educational toys for children.
educational toys for children - Google Search

This reminds me of another similar post, not you CM?

I recall the post you are talking about..