Is a 10-digit business number valid in Ontario?

I fall into the bracket where I don’t currently have to charge taxes and won’t have to for a while still. So I don’t want to get the tax number, because once I do, I then have to start charging taxes.

So what I get from what your saying is the only way I can use Shopify’s check out options (that I pay monthly to have access too) is if I get this number? - Sigh!