Hi @Kathy Harris-Austin ,
Welcome to our forum!
Are you using an Outlook.com account without password and want to create a password to access it on iPhone?
If so, please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. Do you mean Going passwordless? If so, you can refer to the below steps to add a password back to you account.

Hope to help you! If the above doesn't help, it's suggested that you could post your case in dedicated forum for Outlook.com for more professional advice. Thanks for your understanding and support!
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