How can we get USB Medical Card for our wallet for document need to provide emergency service?

That would NOT have the medical history file. The Medical USB card can have that and other relevant documents also that ER can see by plugging in a computer. I did find the info - http://www.co.middlesex.nj.us/Government/Departments/CS/Pages/Aging%20and%20Disabled%20Services/Other-Office-Initiatives.aspx

All you need is your health insurance card. They know who all your doctors are, and can inform the ER if you end up there.