"What I meant about using a PC was, if I were to use C language do I need to interface the microcontroller and the PC"

If you write in assembly language, you need a PC to run a program called an "Assembler" that translates your source code into the binary code used by the processor.

If you write in 'C' it is just the same - you need a PC to run a program called a "Compiler" that translates your source code into the binary code used by the processor.

The system on which you run your development tools (editor, assembler, compiler, etc) is known as the "Host" system.
The PC & MS-Windoze/DOS is the commonest Host for 8051 development; you can also use UNIX etc.

The system on which you run the code that you actually develop is known as the "Target" system.
In this forum, we discuss 8051-based Targets.