You have a few practical options:

• Photograph yourself: Use a cable release or tethered shooting so you can test lighting, pose, and camera settings without another person. A chair helps you return to the same position while adjusting lights.
• Use a practice head: A hair styling head or polystyrene mannequin head on a stand can help you learn light direction, shadows, and modifier placement. It won’t replace a real person, but it’s useful for setup practice.
• Join local group shoots or studio meetups: If any nearby studios, clubs, or photo groups run model sessions, these are great for practicing with real people and seeing how others direct subjects.
• Shoot events or parties: If you’re comfortable working in active environments, casual event photography can help you practice portable flash setups and interacting with people.

For pure lighting practice alone, self-portraits are usually the most useful, because you’re working with real skin, facial features, and body shape. Then move to group shoots or events when you want to practice directing people.