Best AI for coding?

Yes i know, this has been probably asked here plenty of times, but i wanna ask this anyway since AI seems to change almost every day and i wanna ask for my specific case here.

So, i am working on multiple(mostly hobby-related) projects and some of them are pretty large. Those are written in C++ and i'm working with Visual Studio.
I was using ChatGPT o1 most of the time(not the pro version) and it wasn't too bad. However the more complex and deeper the code/problems go, the harder it is for o1 to give proper answers or it just fcks up things.

My question is now: What would you recommend for large projects?
A dream would be something that is at least as "good" as o1(or better) and which can access my entire project files aka the WHOLE code and provides answer based on it.

Money is of course a thing here, but 20$ per month is not an issue. However i regret paying 200$ for o1 pro without a way to try it before.