i have a question for you: why will you not listen to people who say they do not exist?
i mean, i get you want to be one so badly, but if a large number of users who have studied magick far longer tell you 'i am sorry, but magick does not work this way. it is a neutral energy found in nature. it is not black or white, it is neutral until the caster gives it a positive or negative charge. this energy only effects energy, and as a part of nature, it cannot contradict nature. it can attract luck to you by effecting the energy naturally found in and around you, but this is not a physical change. a spell to transform into anything other than human will not work because this is a physical change, and therefore something beyond magicks control.'
why stomp your feet and refuse to listen?
is it because you saw it in a movie/show/game/book and therefore it's real? funny thing about media created for entertainment, it's fantasy, fiction, not real. reality is boring. real magick is boring. no sparks flying out of wands, no levitating broomsticks, no turning people into newts [insert Monty Python retort] nothing cool you saw in a movie. real magick is energy, on top of that, there is a differences between magick and spell casting, some witches who believe in magick don't even believe in spells! [as confusing as that may sound] they see magick as a natural energy that can change things, like the seasons, or how a caterpillar becomes a butterfly. even technology can be seen as magick to them. those who do believe in spells and cast them also see magick as energy and a key part of spell casting, but they too see it as a natural thing that cannot contradict nature.
i understand when you want something so bad to find out it's not real it can be rather heartbreaking, but this is a sad fact of reality. as we grow, we learn some things aren't possible, some things don't work out, and some things will never happen. the fact of the matter is p [no matter how much you don't want to hear it] you cannot with real magick transform. you. are. human. nothing will ever change this fact.
now, why [if you're still reading this] is there so many spells then? well, because members of spell casters coven can post anything and no one can stop them. people come here for the spells, so unless it's dangerous [advocating self harm] or includes banned language, it will not be deleted. only filed away in fantasy and trick spell sections [aka, not real] with this said, some do claim mermaids are astral beings [as in not physically real, but spiritual like angels, demons, and spirits] so some believe you can work with them and incorporate mermaid imagery into their practice [look into sea witchcraft] but in terms of a physical transformation, no, that will never happen.