You should sign in with your Google account details
If you don't have a iCloud account, you can create one hereTo set up iCloud on a Mac, choose Apple menu Image Added > System Preferences, then do one of the following:
macOS 10.15 or later:click Sign In, enter your Apple ID and password, then click iCloud.
macOS 10.14 or earlier:click iCloud, then enter your Apple ID and password.
If you do not have an Apple ID, follow the onscreen instructions to create one.
Turn on the iCloud features for Safari
Mozilla Firefox
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A guide to set up Firefox can be found here - How do I set up Sync on my computer?
You should sign in with your AppleID account details
If you don't have a Firefox account, you can create one here
