You’ll need you be careful to distinguish the terms Sole Proprietor and Corporation. 

As long as your product is not zero rated you should open an HST account (voluntarily) in order to potentially get HST refunds on HST you pay out on eligible business expenses. 

Hi!
Very exciting times, I am planning to register as a Sole proprietorship, my main focus will be professional services, clients would mostly be international. I'm wondering if I should register an HST and a business number. The federal website isn't quite clear on what constitutes a taxable supply. 
https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/registering-your-business/you-need-a-business-number-a-program-account.html

I'm based in Quebec. 

Thanks!

Question on corporation registration