Non-programmer seeking advice: Building a medical diet app with ChatGPT

I'm building an app to manage my child's strict medical diet, in the hopes of replacing my clunky spreadsheet that tracks protein/carbs/fat for meal ingredients.

Although I have been very impressed with o3-mini-high's capabilities, I'm running into consistent issues that make me question if I can realistically hope to get this thing past the finish line.

My experience with o3-mini-high has revealed some frustrating patterns:

1. When it regenerates the code for js files after i request changes, the code often has undefined functions, leading to compile errors
2. After fixing these errors, subsequent changes often reintroduce the same undefined function compile errors
3. When it regenerates code for all the js files, it often provides some files multiple times and can forget to include others

I specifically subscribed to Plus for the best reasoning and coding, but I'm feeling like I'm hitting a wall.

Question for experienced developers: What strategies would you recommend for non-programmers trying to build and maintain reliable software using AI tools? Am I hoping for too much, here?