how to access account management screen for save passkey

G'day sergio1108,

This link has some good detail: Sign in with passkeys on iPhone - Apple Support

"Save a passkey for an account

Depending on the website, browser, or app, saving a passkey to your iPhone and iCloud Keychain usually consists of steps similar to these.

1. On your iPhone, do one of the following:

• For a new account: On the account sign-up screen, enter an account name.
• For an existing account: Sign in with your password, then go to the account management screen.

1. When you see the option to save a passkey for the account, tap Continue.
2. Your passkey is saved.
3. 

Note: If you want to save your credentials to an external security key or to a different device not associated with your Apple ID, you may be able to select Other Options, Save on Another Device, or similar (instead of Continue). Then follow the onscreen instructions."

Based on the text above, the account management option might appear if you've already set up an account with a website/app, but it also varies depending on the website/app in question. If this doesn't account for what you're seeing, please reply back with more detail about what's happening, and we'll go from there.

Take care.

Hello sergio1108,

It sounds like you have questions about using passkeys on your iPhone. We know how important this is for you, and we will help get you to the right place for answers.

The first thing to try is the Sign in with passkeys on iPhone section of the iPhone User Guide. It may answer some of your questions.

All the best!