Hi goodmorning i am visitor in canada and i have a 10 years multiple V-1 and when i came in at the airport the give me 25 days to stay and if it finish can i get an extension to stay
You can apply for an extension before your current expiry date. Given you were only permitted 25 days at landing, I would expect a quick refusal of your extension. Keep in mind a 10 year multiple entry visa doesn’t allow you to stay 10 years.