The yellow vegetables are carrots, squash, beets, and sweet potatoes. The green vegetables are peas, green beans, and spinach. Prepared commercial baby food is the most convenient to use. You can make your own. Don't add salt or seasoning to the vegetables.
White potato mashed with milk is a good homemade baby food.
Develop the habit of reading the labels on baby foods. Buy baby foods without added extras, such as sugar, salt, thickeners, cinnamon, citrus products, etc. Products such as apple-blueberry combinations contain many different ingredients and are actually desserts rather than fruits. The immature digestive system of a baby is often not ready for these extras. Babies who exhibit allergies should be kept off these combinations for a few more months.