Is 20 years old too old to do online schooling?

I dropped out at 9 th grade and want to at least do something with my life. I did think about GED but I rather not have to go to classes. Also I know it's late but is it possible? I just want to make my parents proud honestly and I dont have anything to do all day but baby sit so that's why I thought about online schooling instead of GED. I want to try to finish high school not online college online high school. My cousin is doing it atm but he's younger.