Can somebody walk me through how drill 4 holes with 0.25" diameter using a router bit size of 0.25" diameter using an autocad , Lazycam(unregistered) & Mach3.It was easy when i had a bit with  size of diameter 0.125"

See page 41 in the Lazycam Manual. It covers drilling.
As far as CAD is concerned you can draw a circle of any size where the holes are located.
Basicaly you select the items representing the holes, define them as a drilling, and then define the motion in LC.

RICH

If you're using AutoCAD 2002 or newer, I have a macro that will do what  you want very easily. It's also does much. much more, and much faster than LazyCAM. Be sure to read the manual.

http://home.comcast.net/~cncwoodworker/acad/downloads/ac2gcv045.zip

You do the holes to be drilled as a point in Acad. Then when in Lcam do a drill cycle to the point.

Hope that helps

Can somebody walk me through how drill 4 holes with 0.25" diameter using a router bit size of 0.25" diameter using an autocad , Lazycam(unregistered) & Mach3.It was easy when i had a bit with  size of diameter 0.125"

If it was easy with a .125 bit it should be just as easy with a .25 bit. You go off center of the drill point. Diameter only matters for speeds and feeds. If you can provide me you machines rigitivity, HP, RPM speed range, Z axis speed and materiel I can give you some suggested speeds and feeds.

You do the holes to be drilled as a point in Acad. Then when in Lcam do a drill cycle to the point.

Hope that helps

I will try this and keep u posted

Let me know if you need help on the speeds and feeds.