Hi everyone!

I've been asking this a lot of places but it seems to me that no one knows the answer. Please help if you know!
Ok, I am a J2 dependent who will be turning to 21 at the very beginning of April. Now, my father will go back to our home country at the end of July but until July I still will have to graduate from the high school which I'm currently attending. Since my dad is subject to the two year home residency, me too. Can I apply for visa waiver (so I can apply for a student visa) independently from my dad? If yes, how should I do that? What happens if I don't get any waiver before my visa expires? Will I considered to be illegal even if I will be waiting for the waiver? But, the main question is Can I (J2) apply for visa waiver independently from my dad? Please answer as soon as possible because my visa will expire at the beginning of April right before my 21st birthday!
Thank you,
Sophie