US Immigration from Canada

Hi, I m wondering if anything in particular needs to be done before leaving Canada and entering the US on a k1 visa. For example:

Do we need to advise Canada Revenue Agency of the move or do anything in regards to taxes?

This is a silly question, but what happens to our Canadian citizenship? Is it something we always have, even when we become a green card holder in the states?

What happens if our Canadian passport expires before we get a US green card, let alone US citizenship years later?

Are we still able to use our MSP healthcare benefits if we are visiting back home in Canada?

Thanks!

Hi, does anyone know if we are able to take university or college classes once we enter the USA with the k1 visa? I know we can t work until we get work authorization, so I thought it would be the perfect time to upgrade with some classes in the meantime.

Hello Everyone, I am getting my citizenship in a week which I am very happy for .

with that being said I wanna bring my family to the US as well.

just wondering how do I start the process and which form am I supposed to fill out?

I'm currently living in Canada and am married to an American citizen. I'm thinking about applying for a marriage green card and was just wondering how long I have before I have to enter the US once the green card is issued. I've read that a green card holder can be out of the states no longer than one consecutive year before forfeiting their status, would the same apply in my case since I would be living in Canada when issued a green card, i.e. I have one year to the enter the US?

Edit: not sure if this is the right forum, but my concern comes from how long I have to find employment, while still living in Canada, once issued the green card. I initially thought I could keep my current job and just work remote, in the US but I no longer see that as a viable option.

I m getting really stressed and anxious now. I just tried to check in on the app for my flight back to the US and for the first time ever, it s asking me for secondary travel doc info (alien resident card or PR card) which I do not have as I m still in AOS. I did a quick google search and some said if you don t have those, you need to check in at the airport with relevant docs.

Has anyone else encountered this before or can give me any insights? I have a valid AP doc with me. Should I just show that at the airport when I check in in person?