When I think of office administrator, I think of an office manager. While I am not currently an office manager, I have done that job in the past when I had recently graduated college. Elements of the job included making sure the office facilities were running smoothly (clean and well-stocked), managing the front desk to welcome guests, and planning office events. I would consider the work to be customer centric in that your goal is to make the experience of everyone in your office a positive one. I would recommend you also learn about other careers in business as well -- I ended up working in operations (helping get services delivered and products made), and human resources (how to attract, retain and develop the people, or talent, in an organization). There are many options out there to explore.