AI Algo Trading Platform Guidance

I want to build a complex Algo Trading platform (web app) using AI. AI will do all the coding. I am the only person involved as I have no technical team. The whole things has to be modular and well designed so changes do not break the whole system. I have the requirements with me. I have technical knowledge as I have done coding also (.NET) and have info on databases too.

Please help/guide me with:
1) Which AI should I use for development such as claude code or cursor or what is the best right now?
2) How to go about designing the user interface also?
3) Guide rails and precautions I need to take when undertaking such as project specially with AI involved. Need to ensure AI stays within limits or bounds and does not overthink.
4) Do I need to use code management tools such as github or any other?
5) Links to videos or other resources that may help me
6) Show me how to keep the system modular so I can experiment quickly without breaking production.
7) I want AI in web-app which will answer user's questions or develop strategies based on user prompts. How to go about it ?

Apply if you fulfill the following :
- Have strong knowledge of AI and have yourself developed complex apps
- You are aware of what’s the latest trend in AI and what models or AI agents are best for coding and UI design right now
- You should be an expert in this field and not a general user using AI for basic stuff

Thank you