We don't have a lot of information about the religious beliefs of the Calusa. Most of what we have come from Friar Juan Rogel, an unsuccessful Jesuit missionary who lived among the Calusa from March to July in 1567. From Rogel's writing, we learn that the Calusa believed each person had three souls. One resides within the body, specifically in the eyes. One occupies a person's a shadow and the third, the person's reflection. When a person dies, their internal soul remains tethered to the body, while the other two enter into the downward cycle of reincarnation until they dwindle to nothingness. According to Rogel, the Calusa found the Christian concept of an eternal soul laughable.

Rogel also writes that the Calusa believed in three gods. The first is the god of the natural order and cosmic affairs - the stars, the seasons, weather, etc. Presumably this god is also the creator. The second god is more earthly, described as the god of human governments. The third is essentially a god of war and was less powerful than the god of governance. Hernando de Escalante Fontaneda, who lived among the Calusa for 17 years after being shipwrecked as a teen in 1549, also mentions another god - one associated with the dead or cemeteries (or perhaps one specific cemetery). The exact significance of this potential fourth god is uncertain.

Fontaneda also mentions human sacrifices though Rogel doesn't. Since all the alleged human sacrifices were Spanish war captives, Fontaneda may be describing the execution of prisoners or war rather than religious ceremonies.

Creek traditions, including Seminole traditions, are better known.

Here, humans have two souls, not three. The upper soul resides in the head or heart (depending on who you ask) and is associated with personality and reasoning. It leaves the body only at death. The lower soul resides in the liver or intestines and is associated with passions, emotions, and the conscience. This soul can leave the body while the person sleeps, with its nighttime activities being remembered as dreams. At death, the upper soul sets out on a perilous journey to the Upper World, travelling along the Milky Way - assuming the person lived a good life and isn't doomed to wander the realm of ghosts. The lower soul generally remains behind, lingering near the body, where it can either cause trouble in the form of disease or be contacted if you know how to communicate with dead.

As for spiritual entities in Creek / Seminole belief, I don't have the book handy that I like to use when discussing that topic and since I'm starting to run short on time, I'll have to leave it be for now and come back to it later. For now, I'll just say that the Creek pantheon of spiritual entities doesn't match up with Calusa's slim descending hierarchy of ruling gods as described by Rogel. Instead there's the Creator at the top, then a wide variety of more earthbound spirits who are more involved in daily affairs of humans than the Creator itself.