So the website offers freshman courses (some of them my student took in high school), then what? If you are in a stem program you will need to actually go to college.
And if you are qualified to actually finish a STEM program you should be able to get financing and parental support. All my college children and grandchildren were/are in AS/BS/MS degree earning programs. Those that needed it, Grandpa, helped support!
Grandpas and Grandmas, put your money to work for immortality; support your STEM grandkids! You will be remembered forever, I've experienced it! I'm a healthy 76, but I already feel immortal!