Suggest a research design.

I am currently doing research assignment which is to design a program evaluation and need to seek advise on some research questions.

As a person is less to seek help from professional, a program is conduct so that the person know when to seek help when needed.

The question asked for type of research methodology and design to evaluate the effectiveness of a program after one year of implementation. There is no Pre-test-Data.

I want to prove that if participants attends the program, the participant is more likely to seek help. If did not attend the program, less likely to seek help.

I am confused as i am using a correlation design. But from my understanding, correlation is suitable for measurement rather than a "yes" or "no" question.

So which research design should i use? Thanks for the advice.