From what I know of canonical tags, they have different values relating to the current page. If in your use case, you will have the same tag on every page then you could use Netlify’s script injection to insert a tag into very pages <head>.
Here is the information you will need for that:
However if you require a different tag for each page, then I don’t think this can be achieved with Netlify.
Are you using a SSG (Static Site Generator)? What you are trying to do could be easily done with something like Eleventy or Jekyll.