"I wanted to know the process to append two additional 8 bit ports in 8051. And I also needed to know the VHDL code for it."

It sounds like you are trying to build your own 8051 "core" in VHDL, yes?

As you can see from the replies you've had so far, this forum is mostly populated by chip users - not chip designers

However, the question has been asked before - do a search for "VHDL" and/or "Verilog" and you will find references to some sources.

There are many IP vendors selling 8051 "cores" these days.

For HDL questions, I think you'll have to go to an HDL forum.

However, if you do just want to find an 8051 variant with extra ports, look at the Triscend E5.