Excellent news! Congratulations.Yeap its called saint bernard lacolle cbsa inspection station.
When you go there, you will be facing the USA side, the us officer will ask you, how r u and what not, u just say i need to go towards Canadian side for the landing purposes.
He will give u a document that states intention to reject entry to states.
You will take a u turn and wait in line on the other side, the cbsa officer will ask you about the details, and will ask your status in Canada and will give you a yellow page that you will have to submit at the office.
That is it, took me almost 3 hours going back and forth and doing the whole process.
I've heard rumors of people saying that at one border crossing you are able to take a u-turn before even being rejected by the US agents. I was looking at the saint bernard crossing on google maps it kind of looks like that's the case. Did you manage to see anythin like that??
Best of luck for your future in Canads!!