When you use “Build Project” inside BridgePoint, the translation (aka model compiler) translates the model into C and then uses the eclipse CDT & gcc to compile the code into a runnable EXE that is put under the Debug/ folder inside the project.
This translation process creates some lightweight architecture that includes a main function that runs the event loops.
xtUML provides two mechanisms to integrate an xtUML Model with Legacy (aka Realized) code. This is an advanced topic that is best approached after you have a solid understanding of the fundamentals of xtUML modeling, execution and translation.
We have a self-paced online course called “Modeling with xtUML” at https://xtuml.org/learn/on-line-courses/ that will teach you these fundamentals and introduce the topic of integrating with Realized code in Module 18.