My mom doesn't think vastly works.
I wish to further my education as vastly as possible in all aspects of life.
Your mom is right.
As much as possible.
To the largest extent possible.
Either of those might work. You can try a few others.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.