If you’re under 18 do you get all your taxes back

[SweetieJean]

Not necessarily. Depends upon the amount and type of income.

[BobinCT]

It depends on how much you earn, how you earn it, and whether some can claim you as a dependent.  If you ARE eligible to be claimed as a dependent and had only W-2 income the first $6350 of earnings would be free of income tax.  Social Security and Medicare taxes are never refunded..