I DID do supervised medical weight loss though mine was a six month program. But since they were all booked out in December my surgery got pushed to January so it was actually an eight month process. And I used https://www.bariatriceating.com/blogs/recipes for recipe ideas when I was dieting. I found several recipes that I really liked. My favorite is a no noodle lasagna. It's delicious!
But, you CAN substitute. For example, say you want stir fry. But you can't have rice. So... you use cauliflower rice instead. And for the teriyaki sauce you just use a sugar free one (I use G. Hughes. They also make sugar free bbq sauce. They sell it at Walmart). Also, they have low carb tortilla bread that you can use for sandwiches. They're with the tortillas, usually. Also, cheese crisps are a great replacement for chips, crackers, and/or croutons.
Hope this is at least a little helpful...