Dear i want to use micro controller c8051f350 how to connet it to pc kindly tell the right way how to connect waiting for your reply
That obviously depends on what problem you want to solve. And what interfaces your PC has.
You could get a MAX232 and use the UART to connect to the PC. In that case, Google will have a huge number of examples of how to do it.
Or you could get a USB-to-serial cable with logic-level signals in one end, for connecting to the RX/TX pins of your processor, and with a USB device connector in the other end, for your PC.