You can major in anything (including computer engineering) and be pre-med.
Putting that aside, UF is flexible around changing majors. Many of the courses you’ll need for Biology, or engineering will be similar the first few semesters.You’ll need to take Chemistry, Calc and Physics. Take that first year at UF to explore other majors while taking your core classes, before making your final choice.
By the way, a BS in Computer Engineering is all that’s required, major employers include Apple and Intel for CompE’s at UF. A lot end up working on the west coast…
Good Luck and Go Gators!