My dad says I should put a few hundred dollars in bitcoin now, and take it out when I'm 18

As the title says, my dad is saying I should put 300-400 dollars in bitcoin and when I'm 18 (or around it) I take it out and use the money to help myself start my life. Is that a good idea? Would I have made enough money to do have any real effect? Would I lose any money? I appreciate any time spent reading this and/or helping.

I'm in highschool btw