Camunda 7 Debugging

Hello, can someone explain to me how to start the application up and debug the working flow ? I cloned the application from here:
And I want to debug the application, I don’t want to run the tests, I built the application with no errors with mvn clean install and build and then when |I want to start the application I get the error like not specified database or driver but that is running the tests i want to run the engine.