Hi, Leeneia-
MIDI ports on computers are long gone, probably since about 2000. They used to accommodate joysticks and other game controllers. I can't recall how many pins they had - they looked like a video or serial port.

Nowadays, MIDI keyboards are connected to computers by USB. Some keyboards have USB outlets, but I think most still have the round connectors that MIDI keyboards have had for years.

If you Google or search Amazon for MIDI to USB, you'll find what you're looking for. Cables run from eight to forty bucks.

Hope that helps.

-Joe-