Post Baccalaureate or "Post-Bacc." students must apply to OSU as a Post Bacc student. Once you have applied, been admitted, have indicated you will be attending OSU, and set up your ONID username and password, you can add DPP to your admission status for free!
Once admitted to DPP, you would be considered a student at OSU and any Oregon and Hawaii community college partners. Upon being admitted, you have 10 terms or 2 years before you have to take a class at OSU. During those 10 terms you have an "active student status" which means each of those 10 terms you would be able to “dual enroll” at both OSU and your partner school, or only take classes at OSU, or only take classes at the partner community college; it all will depend on your situation and what works best for you.