How do I launch a survey from an external system?

I know that is a broad question, but I have been going over the API documentation and I am at a loss as to where to begin.
Here is exactly what I want to do and I hope that someone can point me in the right direction.

1. Create a survey directly in Qualtrics


2. User logs in to my external application


3. User clicks a button in my application and the survey is "launched" for them to complete


4. When the user is done with the survey, they are redirected back to my application


5. My application needs to be able to call Qualtrics to receive the completion status of the survey for a specific user