How to switch career from 1 field (i.e. Administration, Operation, Customer Service, Procurement) to Information Technology (IT) field?

because are experiance in all stream so no problem because our compony various department esperiance

If you are qualified in any of the field you mentioned and gained experience, then you shall acquire additional qualification in IT to develop better tool of your qualified area to support your area. This is called Subject Matter Specialist. You shall try through this. IT is need of SMS like you professional