Is the way I write my grad school personal statement supposed to be totally different from the basic essays I turn in for my freshman English 101 class?

I'm a first-year undecided major and I'm already looking at grad school requirements because I want to get into a competitive program eventually. I've been googling tips on personal statements, but every article talks about 'academic voice' in ways that sound way too fancy for what I'm used to writing. I'm honestly just terrified that my current writing style is too simple and won't get me accepted anywhere later on. Can you explain the actual shift in expectations between undergrad papers and graduate applications so I know what I should start practicing now?