Much of how we understand the nature of the Trinity comes from Greek thought. And in particular, the terms: person and persona.
We talk about the Trinity as three persons, which evokes three individual people. But we also speak of them as personas, or masks, that can be worn by the same person.
This language can be confusing when left at that level, but we ought to consider that these words are not only of the same root, but kind of say the same thing.
This might seem weird in a culture of hyper-individualism, but three persons being one is not as mind-bending an idea when we aren’t obsessed with keeping everything separate, specialized, and different. When we entertain what we share in common.
We is as natural a concept as I.