Will I be at a disadvantage? (very few extracurriculars due to circumstances)

Not at all, I worked at my family’s restaurant (with very few significant ECs and 0 volunteer experience) and I was accepted to rather selective colleges (Tufts, Vandy (transfer), Penn (transfer)) with far less impressive stats than you (2140 SAT/3.7 GPA).

I would base your essays on how helping support your family influenced you.