Comprehensive sickness insurance

Hi, my name is Dayana, I am 19 and I am bulgarian. My situation is I came August 2007 with my family and we apply together for certificates that will allow to work in UK. Board agency gave my father yellow certificate and me and my mother received blue certificates. This year I will apply for PR but I read that as student I need Comprehensive Sickness Insurance. When I entered UK I was 14 and I have been 2 years in secordary school and after that from 2009 to this year and next year I am in college. I have letter from my secondary school that comfirms that I have been student there for these 2 years and I have from the college the certficates. I know that my father can include me as his EEA national family member but I find a paragraph in a EAA3 form that state:

You must provide either a private comprehensive sickness insurance policy document that covered for medical treatment in the majority of circumstances, or a European Health Insurance Card (EHIC) that covered the 5-year period of residence in the UK.

I have this card before to come to UK and it's still valid, my question is can this card be use unstead of comprehensive sickness insurance.

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