iCloud Note sharing Key Chain

Hey P3aB33,

You mention your notes don't sync if you're using cellular data only. If you haven't already, make sure you have cellular data turned on for them: View or change cellular data settings on iPhone - Apple Support

Set cellular data use for apps and services

Go to Settings  > Cellular, then turn Cellular Data on or off for any app (such as Maps) or service (such as Wi-Fi Assist) that can use cellular data.

If a setting is off, iPhone uses only Wi-Fi for that service.

Note: Wi-Fi Assist is on by default. If Wi-Fi connectivity is poor, Wi-Fi Assist automatically switches to cellular data to boost the signal. Because you stay connected to the internet over cellular when you have a poor Wi-Fi connection, you might use more cellular data, which may incur additional charges depending on your data plan. See the Apple Support article About Wi-Fi Assist.

For iCloud Keychain not syncing, the steps under "If you don't see your iCloud Keychain items" should help to get those passwords syncing between your devices: If iCloud Keychain won't turn on or sync - Apple Support

Let us know how it goes.

Take care!

Set up iCloud Keychain Make your passkeys and passwords available on all your devices with iPad and iCloud Keychain - Apple Support

Set up iCloud Keychain on an additional device

When you turn on iCloud Keychain on an additional device, your other devices using iCloud Keychain receive a notification requesting your approval of the additional device.

On one of your other devices, approve the additional device. Your iCloud Keychain automatically begins updating on the additional device.

To approve iCloud Keychain when you don’t have access to your other devices, follow the onscreen instructions to use your iCloud Security Code.

And then share website passwords from iPad to Mac Share passkeys and passwords securely with AirDrop on iPhone - Apple Support

The notes will be shared when notes box is turned on both devices Set up iCloud for Notes on all your devices - Apple Support

Read About using iCloud Notes on Mac - Apple Support

Mobile network is slow comparatively to wifi connection , turn off mobile network View or change cellular data settings on iPhone - Apple Support

You can share network from Mac to other devices using ethernet so that network speed becomes fast Share the Internet connection on Mac with other network users - Apple Support

Hey P3aB33,

Your iCloud Keychain items do not sync unless connected to a Wi-Fi network, correct? If so, make sure all the devices are up-to-date. Software updates include new features, security updates, and fixes.

If you continue to experience the issue, contact Apple Support here: Get Support. They should be able to further investigate and help you with a resolution.

Take care.