What is the relation between your two entities? You can definitely use two entities in a single page. But how do you relate them? As you described, one entity goes as data source to a data view. Now you can use second entity inside this data view by setting an association with first entity.
When inside data view, on right side properties tab, go to connector. You will see options to connect your associated entity with parent data view’s entity
What exactly are you trying to achieve? With a little more insight into your use case i am sure we can help find the solution for you.
A page in Mendix can only have one context object, trying to have multiple is not the way.