My son is not a dependent, age 21 and lives on his own and is not in school. I pay his health ins and emt training. Can I deduct?

Simple answer: No, because he's not your dependent.

There is something known as a Medical dependent :

If your close relative cannot be your dependent because he had more than $4,050 of gross income, but otherwise would have qualified as your dependent (basically that you & other family members provided more than half his support), then you can include in your deductible medical expenses any qualifying medical expenses you paid on his behalf just as if he was your dependent.

EMT training would not qualify