I'm not sure what the best way to approach this would be for your mind specifically, but there are a few different ways to talk about this that I think are all different perspectives of the same idea.

From a scientific perspective, your brain contains many layers of physical forms (some from very early on in our evolution or "the lizard brain") and others, such as the pre-frontal cortex, which are more recent evolutionary additions to the brain for what we would think of as "higher faculties". Each layer of the brain has different purposes and communicates in different ways. Language, for example, is a very specific region of the brain where as other regions of the brain may communicate with emotions, or symbols. During our waking life, we are often focused in the language centers and generally involved in the world around us and the future/past worries we have to focus on. When you sleep, you are not consciously focusing your attention, and the subtle aspects of your brain are more free to interact and communicate. From that perspective, you could say that your brain is communicating to your "higher mind" the things which it has been working on in the "subconscious".

If we take further down the rabbit hole, we are coming to understand that all of what we call the universe is essentially a more-or-less infinite expression of intertwined and self-organizing energy, which is experienced in limited capacity by the human mind. We also are coming to understand that what we call the universe is likely not the only realm/dimension that exists. We're coming to understand that quantum particles behave in what we can only refer to as magical ways - existing in multiple places at once, jumping across space instantaneously, etc. Quantum entanglement is a spooky fascinating phenomenon in which particles that are intertwined, no matter where they exist across space time, can influence each other instantaneously with no direct contact.

You could wrap all of this up into a spiritual package, if that speaks to your understanding. We are all manifestations of (divine?) consciousness and we are occasionally graced with instantaneous understandings (realizations, "light bulb moments"). It only makes sense that we don't pay attention to this much in waking life, but during our vulnerable sleep states, we are more receptive to the subtle energies of the people, world, or even spiritual energies around us - or even those of our own inner mind.

Any way you slice it, it's not a terrible unrealistic thing to say that our dreams can communicate with us in meaningful ways. In fact, your sleeping brain experiences dreams almost indistinguishably from waking reality (this is why sleep paralysis is necessary - otherwise, you would physically enact your dreams). Sure, sometimes they are a product of chemicals or random firings, but it seems the more attention you pay to your dreams, the more they begin to hold real meaning. I tend to believe we wouldn't dream at all if it didn't serve a purpose. Maybe you could try keeping a dream journal and see where this path leads you. Sleep on, dreamwalker. <3