Online classes with intent to go to university at a later time

I’m looking to start some online classes with plans to eventually transfer the credits over to a university. I live in Colorado, so it will most likely be the University of Denver or CU. I’m currently playing professional baseball, so during the time that I’m not playing (fall semester), I’d also like to take some classes at a local community college to knock the basic pre req classes out.

First of all, is this possible? And which online education organization/school would be best for this? I’d like my major to be business/management…

Any suggestions? Thanks guys.