Help with weight loss?

Hello! I'm 21, 5'7, and I weigh 347 lbs. I know, I'm super obese. My boyfriend and I have been TTC for just over 2 years now, he has decreased motility at 30-40% but I feel like my weight is a very big factor in our infertility. I really want to get my health back on track and get my body at a healthy weight to get pregnant. We're looking into IUI but I want to try losing weight first, and I feel that they won't go through with it because of my weight 😔 I was wondering if anyone has tips/tricks for a super picky eater to lose weight. Right now, I'm very sedentary, I don't exercise. I plan on starting to do 20-30 minute walks daily and increase my water intake, even though I already drink around 32oz a day. I'm a picky eater - I don't like most vegetables or salad. It's even harder for me to lose weight as I have hypothyroidism. I'm not currently on my medication due to not having insurance but I'm in the process of starting it again. Google says my MBR is 2,381. So if I reduce my daily calorie intake to 1500 and start exercising, is that a good weight loss plan? Any information would be appreciated!