If you are registered to collect GST/HST, then you need to submit a GST/HST return through the Canada Revenue Agency (CRA) website. You can read more about it on this CRA page: https://www.canada.ca/en/revenue-agency/services/forms-publications/publications/rc4022/general-info...
You would submit any GST/HST that you owe with the GST/HST return.
If you need assistance with your GST/HST return you can contact the CRA for help, or you can have your taxes done by a tax expert at TurboTax Full Service. They will prepare both your personal tax return and your GST/HST return for you. You can read more about TurboTax Full Service on our website here: https://turbotax.intuit.ca/tax/pricing?preselectedPills=pnp-pill-self-employed-freelancer
