My account is in canada, i want to set up receivables and payables in USD, can someone shed some light?

You need to use QBO Essentials or higher to enable the multicurrency feature but you can't use QB Payment to accept non-CAD invoices. You can use a 3rd party payment processor to integrate with QBO.

Good morning, elie-skiptick-co.

Thanks for connecting with us here. In addition to the valuable information provided above, here a are a couple articles I feel you'd benefit from.

1. Take and process payments in QuickBooks Online
2. Set up and use Multicurrency in QuickBooks Online 
3. Multi-currency FAQ

I hope these help! Feel free to reach back out if you have any other questions.