There is no tax treaty to avoid double taxation:
https://www.canada.ca/en/department-finance/programs/tax-policy/tax-treaties/in-force.html
So basically you need to sever all ties with Canada that might give them a reason to argue that you are liable to tax :
- no local accommodation (including a relative's place that you would regularly go to)
- no trading / making any money while in Canada
- no spending more time in Canada than in Belize
- no vehicle registered in Canada, no valuable belongings there... (the vital interests argument)
- be able to prove that you are indeed a tax resident somewhere else : that is the part you need to check with Belize