PhilBoy

Hello, I'm working on a desktop application development project(specifically a desktop simulator tool) and this simulator was developed with Object Pascal. I'm trying to understand the architecture of the simulator and improve the features of the simulator. I have very basic knowledge of OOP but I don't know what I need to learn to be able to do the task I described above. Can anyone offer a learning roadmap to be proficient enough to do the task above?

To All, Thank you for your suggestions. I have already read the book by Marco Cantu but it wasn't satisfactory. The book by Marco Cantu does not offer a beginner a helpful way to understand how applications are developed from scratch in Delphi RAD Studio. Because I have very basic knowledge, I was wondering if anyone could recommend a roadmap of topics in Software Architecture and Object Oriented Programming/Design that will help me understand a methodical approach to understanding how to characterize and modify the simulation application I'm working on. I am looking for material that will help me learn app development using Delphi RAD Studio. I'm essentially trying to learn software architecture and OOP/OOD using Delphi RAD Studio.