How do I develop administrative skills?

You start developing administrative skills in high school. Following a schedule, using a computer, time management, organization, and collaborating with others are life skills that apply to your future education and career endeavors. For general administrative skills, such as task prioritization, preparing reports and documents, filing papers, and interacting with other people, the best way to develop those skills is to practice every day. You can expect some degree of on-the-job training, especially with entry-level positions, to teach you the specific skills you need for a particular job or employer.