yes you can claim dual citizenship, and to make things simpler for you, enter / leave USA with your US I.D./ travel doc
If you were born outside Canada and one of your parents was a Canadian citizen when you were born, you need to apply for a citizenship certificate to prove you are a Canadian citizen.
contact the Canadian embassy, high commission or consulate responsible for your area, to obtain an application, here's a list
provide clear and legible certified copies of your documents
send two (2) identical photos taken within the last 12 months on white background
A birth certificate which lists your parents (issued by responsible government authorities in the country where you were born)
Proof that one or both of your natural parents were Canadian citizens when you were born
Two (2) pieces of personal identification, such as a driver’s licence and a health insurance card
Other documents, such as a marriage certificate/divorce certificate and/or a legal name change certificate (if applicable)
After you get your certificate you can only avail from the healthcare system in Canada if you maintained a residence within the Canadian land.
let me know how things turned out with you and if my advice worked out for you.
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