Will I be able to find any adapter to USB?
Sim
I do not think it's a serial port as there's too much pins. It's used to plug a very old controller.
É um conector de porta de jogo
The game port, originally introduced on the Game Control Adapter, is a device port that was found on IBM PC compatible and other computer systems throughout the 1980s and 1990s. It was the traditional connector for joystick input, and occasionally MIDI devices, until replaced by USB in the 21st century.
Fonte: Porta do jogo