What is your status know? Normal visitors can stay 6 months have you applied for an extension? If all that is in order you have 2 choices: apply inland or outland spousal sponsorship. Inland will allow you to also get an owp but you shouldn't leave the country during sponsorship. The US citizenship probably would allow you to leave Canada but wouldn't recommend it. The owp would arrive a few months after you submit your application. You could also apply outland. With outland you can live in Canada or another country but you don't qualify for an owp. There is nothing limiting your travel in and out of Canada. You can work in another country if you have the permission to do so,