Prepare all the ingredients as listed above.
Prepare cucumber-lime water: Mix cucumber slices, lime wedges, and water. Chill before serving.
Preheat the grill or grill pan over medium heat. Preheat the air fryer to 400°F (205°C).
Prepare air fryer fries: Toss potatoes with olive oil, and black pepper. Air fry for 20-25 minutes, shaking halfway through, until golden and crisp. Serve with ketchup.
Season the tilapia with cumin, cayenne, and black pepper. Drizzle with olive oil.
Grill the corn on all sides until nicely charred and tender. Spread with oil, season with pepper.
Grill the fish to an internal temperature of 145°F (63°C). Cut into pieces.
Prepare tacos: Warm taco shells on the grill if desired. Fill taco shells with fish, radish, and cilantro.
Serve the tacos with lime wedges, fries, ketchup, grilled corn, watermelon, cucumber-lime water, and dates.