Parent cosigned student loans are a bad idea for both the parent and student. Also, since you have a younger sibling, you do not want your parents to stretch their household finances to the maximum, since having to drop out part way through due to running out of money, or having your younger sibling resent you for taking all of the college money your parents can give, would not be a good thing.
PhD in physics does not guarantee a job in physics research, due to the surplus of PhD graduates relative to the number of research (and academic) jobs in the subject. However, physics graduates’ quantitative skills often do allow them to enter computing or finance jobs.
University of Florida is a perfectly good school for physics:
https://catalog.ufl.edu/ugrad/current/liberalarts/majors/physics.aspx#2
Note the offering of enriched/honors courses. Also, physics majors tend to be among the more intellectually ambitious students at any school.
However, be sure to factor the cost of a mandatory summer session into the cost of any Florida public university:
https://catalog.ufl.edu/ugrad/current/regulations/info/graduation.aspx#summer