My grandfather had some money that is put up in an account then my dad died before he could get to it I just turned 18 what can I do?

I'm guessing from your statements that there was no will.  You could go to the courthouse and asked to be named administrator of your grandfather's estate, but if it has been a long time since your grandfather died, the account may be at a point where it's going to be turned over to the state as unclaimed property.  You would then be able to apply to have it turned over to you.