With your proof of citizenship, you will not be denied entry.
Apply for SIN number (same as social security number) after you arrive in Canada. Bring your birth certificate too, but they will likely give you a SIN number with proof of citizenship only.
Tax status? I do not think you need any tax status prior to earning income in Canada.
To import your personal items without paying duties/taxes, use Forms B4 and B4A to list all items you bring with you on your first arrival, and use new copies of Forms B4 and B4A to list all your items that will arrive later via mail or via your future entries into Canada. You must present these lists on your FIRST arrival---changes to those lists will not be accepted after first arrival. See
http://www.cbsa-asfc.gc.ca/publications ... 5-eng.html
You may be asked to show proof of your funds to cover living expenses such as rent, food, clothing and transportation for a six-month period.
More info at
http://www.cic.gc.ca/english/resources/ ... /index.asp (You do not need the Canadian immigrant visa and Confirmation of Permanent Residence referred to in the link above, because you have proof of citizenship)