What is the best way to structure these use cases?

Question

At the moment, I have defined 3 different use cases that are really just 3 steps in a business process ...

Say I have a list of people, and all these people are interest

Answer 1

Write them as separate use cases. Only a use case that clearly adds value is of use to its actor. I'd say that all of the named UCs add such value and are self-standing. However, without knowing your domain I can not be sure. Maybe they form a single UC. This needs a detailed view.

Extend/include are bad design in UML (means OMG did not do a good job here). Trying to use E/I is almost always a sign of trying to use functional decomposition. But use cases are about the absolute opposite: synthesizing of functionality.

If necessary use pre and post conditions to control if a use case can be performed only after another one.