Choosing an Officiant : What you need to know

All Seasons has Officiant that are legal and reviews upon their services to see who is your best suit to choose.

You will want to think about customizing your service if being religious/non-religious. Their cost will also be important to know if it fits your budget too. Just as a vendor, you want to feel that connection/vibe to know they are right to work with you.

They don't need to be registered with the city. Anyone registered as an officiant in the province can do it. If you're looking for a secular non-denomination officiant, look up the Humanist Association of Canada.

In Ontario, only a Justice of the Peace or a licensed religious official can marry people. Any officiants offering their services have to meet one of these criteria (usually non-religious officiants are affiliated with more liberal sects, they can tell you which ones), but yes in order to marry you, they have to be licensed.
You’ll also want to get a vibe of who they are and if their style would mesh well with yours. Knowing the level of religion you want included or how much personal details you want will help you narrow things down a bit.