Issues re crossing the border…?

Do you have a criminal conviction in your past?

Canada, like most countries, has laws excluding visitors with criminal convictions  in their past.
 
This would include things like:  theft, assault, manslaughter, dangerous driving, driving while under the influence of drugs or alcohol, or possession of or trafficking in drugs or other controlled substances — and more. Some are major and some minor.  Here are some links that can help you understand how you can still be admissible to Canada: