Personally I think 4 months is way too early to start.. best to wait at least 5.5 - 6 months.
You can try giving fruits eg, avocado, banana, dragon fruit, pear, steamed apples, peach strawberries, blueberries, papaya, mango, kiwi. Or vegetables like carrot, broccoli, sweet potato, asparagus, pumpkin, cauliflower, zucchini, peas, kale, brussel sprouts, corn, chickpeas.
Or grains like quinoa, lentils, brown rice, couscous, oats.
Read more