Your project is very cool! But the standard library *.h is not enough. Unfortunately, without transformations, you cannot compile any project and get a good result. There is a lack of readability in the output code. However, these shortcomings are not so important. It would not be bad to create a C# language

Some modifications have been made to improve, but the completion is still too far ...

I completely forgot
Now you can compile asm files using the FlatC and get debug information in x64dbg format:
fc.exe /debug file.asm