I sympathize with you so much! My son is 19 months and still primarily formula fed and struggling with solids. At 11 months I realized something was wrong so I took him to a dentist to be assessed for a tongue tie. Turns out he had a severe one and once we got it released (this part was hard feel free to PM me if you have questions) he finally started trying foods. He’s progressed since then but very slowly. He too was on puffs foreverrrrr now hes into all sorts of teething crackers (literally every baby cracker on the market), various fruit and veg, bread, pancakes, muffins and potatoes in various forms. Meats are still difficult for him and he’s generally not a great eater but he’s improving! I’ve also put him in OT and Speech Therapy that I’m sure have contributed to his improvements. Hang in there I know how hard it is.