I had such a hard time initially to start IF. Like you I am a morning person. It is impossible for me to not eat in the morning. But I started very slow and gave myself a lot of time to get into 14 hour fasting window. I first did a 12 hour and gradually increased the fasting window to 14 hours. Some days I do 15 hours but then that is the max fasting window I could do. The first thing I have in the morning is a glass of warm water. After some 20 mins have my coffee and rusk. Later I have breakfast. I will not get headaches but will be giddy if I don't eat in the morning. My eating window is 8 AM to 6 PM. Also my last meal before the eating window closes would be something rich in protein and fat that helps me stay full till I go to bed.