How do I know this is a legit business to work for?

So I interviewed and got offered a job for a small start up company to be a content creator/media buyer, it all seems pretty good and legit to me. The company is a start up so it’s new and there’s not really any information for me to reference online.

With this said is there any way to verify a small business? Somehow legit check it?

I’m just a little anxious about it because this is my first time working with/starting with a small company. As any job goes I need to provide my SIN number, any advice before I do this?

Also don’t know if this makes any difference but I live in Canada :)

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