In a large mixing bowl, combine olive oil, lemon juice, minced garlic, paprika, ground cumin, ground coriander, dried oregano, salt, and black pepper. Mix well to make the marinade.
Add the chicken cubes to the marinade and toss to coat them thoroughly. Cover the bowl with plastic wrap and let the chicken marinate for at least 30 minutes in the refrigerator. For best results, marinate for 2-4 hours.
If you're using wooden skewers, soak them in water for about 20 minutes to prevent them from burning while grilling.
Preheat your grill to medium-high heat.
Assemble the kebabs by alternating the marinated chicken, red bell pepper, green bell pepper, red onion, and cherry tomatoes onto the skewers.
Brush the grill grates with some oil to prevent sticking. Place the kebabs on the grill and cook for about 12-15 minutes, turning occasionally until the chicken is cooked through and the vegetables are slightly charred.
Once the kebabs are done, remove them from the grill and let them rest for about 5 minutes before serving.