You can either log-in with Google account (which you most likely already have) or via 2fa mechanism where they send an expiring login link to your e-mail address.
There are no password and therefore nothing to hack.
Having no password doesn't mean it can't be hacked. Maybe Notion won't end up in a haveibeenpwned email, but that only addresses half of a single one out of three of my objections to web applications.
You can either log-in with Google account (which you most likely already have) or via 2fa mechanism where they send an expiring login link to your e-mail address.
There are no password and therefore nothing to hack.