Collect first/last name with user activation

We have an application that only specific people should have access to. An internal admin will create accounts for these users, but we don’t know their names when creating the accounts (only their email addresses). However, the users will need names associated with their accounts.

How do I let users add their first/last name when activating their account?

Okta Dashboard has the ability for users to adjust their personal details. So you can instruct them to go there after they activated their accounts