Here are Oncord's full go-live instructions for reference:
https://www.oncord.com/resources/learning/tutorials/settings-and-config/going-live/
Assuming you've already registered a domain name - The company you registered your domain name with will provide a portal that allows you to change the "name servers" that your domain is set to use.
If you're having trouble making this change - I'd say hit up their support team, and they'll be able to assist you.
For a single contact - You can change the user's password via their contact profile. After you manually set a new password, there's a checkbox "Request change of password on next log in". It's worthwhile checking that there are no duplicate contacts using the same email with a password, because that may confuse things.
If you need to handle this for a lot of contacts in bulk - there's a tool "Update Profile Email", which is available via Dashboard > Customers > Contacts, from the menu at the top of the page. This will create a drafted email for you to bulk send out (with auto-login links - so don't forward the e-mail).
Oncord doesn't support 2-factor login for general contacts trying to access a login-restricted website page sorry.
2-factor login is just used for administrators logging into the Oncord Dashboard.
Worth noting - If you're embedding a third-party booking platform on the website, in this situation I'd say the booking app would likely handle 2FA login, rather than Oncord.
@Jason Related: Can confirm we have someone working on a public API at the moment, along with the developer experience for integrating with Oncord as a third-party application.
@beckiehawk Agreed. Very keen to get this resolved.
During early days of "Synergy 8" we mostly operated in Australia, New Zealand and other countries where 'tax inclusive' pricing was the standard.
It's quite a lot of work to make the change, but I can confirm this is something we've already put quite a lot of thought into. It's a high priority, and absolutely something we're keen to tackle for you 
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