Can my phone be off when I am updating my watch . Also it says is gonna take 2 hours is that normal

Hello Penelope1694,

Welcome to Apple Support Communities!

We want to help get your Apple Watch updated to the latest version.

We see you viewed the Apple Support page for Update your Apple Watch - Apple Support

This section can help answer your question:

"Get ready to update

First, make sure that your Apple Watch is compatible with the latest software: watchOS 8 is compatible with Apple Watch Series 3 and later and Apple Watch SE. Upgrading to watchOS 8 requires iPhone 6s or later running iOS 15 or later. Find your Apple Watch model.

Next, check these things:

1. Update your iPhone to the latest version of iOS.
2. Make sure that your Apple Watch is at least 50 percent charged.
3. Connect your iPhone to Wi-Fi.
4. Keep your iPhone next to your Apple Watch, so that they're in range. 

It could take from several minutes to an hour for the update to complete. You might want to update overnight or wait until you have time."

The link you visited has the exact details: Update your Apple Watch - Apple Support

So please keep your iPhone powered on and near your Apple Watch during this time. Depending on the connection, yes it can take some time or a few hours.

We hope this helps answer your questions about updating the Apple Watch.

Cheers!