Want know more about Oil & Gas teachnician

Hi,
Im just graduated last year… With a diploma in mechanical engineering… I looking for a job now… I prefer oil and gas field technician… Im not sure there is how many types of oil and gas technician? What is the future of oil and gas technician? How do i start if I want to involve in this career… I hope anyone with experience can help my out with this so i can set my goal… Thx… Ur answer is very important to me… ^^