Equivalent Circuit Diagram and Design Software for PIC12F675 Microcontroller

Sir,  i have two questions

 

1) i like to see the equivalent circuit diagram of pic12f675 microcontroller.Circuit Schematic inside the chip . Is it possible? if yes then tell me where i could find it.

2) how they designed this chip circuit? which software is used? Where i can learn this?

I've tried checking the datasheet of the microcontroller but it seem to lack a schematics part.

You are unlikely to ever see a full schematic, look at the component count for a chip like this, even for this part it will be enormous. Block diagram is the best you will do, and it is proprietary information you are after anyway.
There are reverse engineered microprocessor cores for a number of architectures suitable for putting in an FPGA, have a look at some of them, it should give you an idea of what is involved, see https://en.wikipedia.org/wiki/Soft_microprocessor
As far as designing chips is concerned, there is a lot of EDA software available, see the Wikipedia article at https://en.wikipedia.org/wiki/Electronic_design_automation
There is some freeware, if you want to dig a little deeper, for example, http://opencircuitdesign.com/
As always, searching the WWW will turn up a lot of information.
Cheers,
Richard