For an introduction to marketing concepts and techniques, check out Digital Marketing All-in-One For Dummies (For Dummies, 2020) and Social Media Marketing For Dummies (For Dummies, 2020). For a brief overview of venture capital, visit https://www.entrepreneur.com/encyclopedia/venture-capital.
Consider joining a high school or college chapter of DECA (https://www.deca.org), a nonprofit organization that hosts competitions, educational conferences, and leadership training programs for students who are interested in careers in marketing, finance, hospitality, and management.
Others methods to explore this occupation include talking with marketing professionals about their careers, studying past advertising campaigns to see why they were successful or failed, creating a marketing campaign for a real or imaginary product (and testing it out on your friends and family), and visiting the Web sites of professional marketing associations.