So you need to do some research on your own first. https://michiganross.umich.edu/undergraduate/bba/admissions
This will answer some of your questions on the first page alone. Take the time to go through the website to answer your questions.
But to answer your general theme question. No, you don’t need Ross to enter the business world at Michigan. Not at all.
https://michiganross.umich.edu/undergraduate/opportunities-and-electives-for-all-UM-students
https://lsa.umich.edu/bli
One program my engineering son did in the rising sophomore summer after getting a $10,000 grant from this program. His mentor was a tech start up specialist.
https://www.optimizemi.org/
$5,000 grant here to help start a tech club at Michigan that led to a full blown out tech conference, one of the first in the Midwest.
He is a rising Junior and currently doing an international internship with a known tech company and he is on the Practice Management team. Funny thing is two others that hired him in this company are Industrial engineers (son is an industrial engineering student).
So no you don’t have to be at Ross to get business experience at Michigan. Instead of engineering you could of change that to just about any major.
The cool thing about Michigan is if you want it, then go do it. No one is stopping you and they will help to no end if you put the wheels on motion.
Don’t companies need to know how to do research? Your analytical thinking is sorta huge for business BTW. They aren’t expecting you to run a business at this point. Think hard about the parrelles between your experience and the business world. It’s there.
I would also call or reach out to Ross for things you can’t find on the website. I assume 99% of it is on there.