PCB Designing Using DXP Protel

I am designing a two sided PCb but i am confused that how to define drill sizes or how to create it?

Not sure exactly what your asking, and I don't know Protel.

1st. Hole sizes are usually defined in the datasheet for the parts.
2nd. Hole sizes are defined as finished hole sizes for 2-sided boards.
3rd. You might ask you PCB house what are typical finished hole sizes.

I use Protel 98SE and immagine it to be similar to DXP.
Pad and hole sizes are predefined in the footprints. Once placed, a pad can be changed by right-klicking on it. In the pulldown menu under "Properties" the pads parameters are listed. E