I am on my parents health insurance and do not have my own personal coverage do I still need a form from the insurance marketplace

[richmangang]

Or the IRS

[Vanessa A]

It depends.  If your parents are claiming you as a dependent, then NO, you do not need to enter anything on your return regarding health insurance.  

If your parents are not claiming  you, and the insurance is through the marketplace, then you would need to enter their 1095-A on your return.   You would then check the box that says I shared this policy with another taxpayer and then enter their name and ssn. Then you would ask them how much of the premiums they allocated to themselves.  You would take the remaining amount on your return.  So if they allocated 75% to themselves you would claim 25%, if they did 100% you would claim 0%.