My series 6 gps watch does not work with my cellular data from my iphone

Your Apple Watch can never use your iPhone’s cellular data directly. The Apple Watch works in one of these two ways:

• If you have a cellular Apple Watch, it may create its own cellular connection independently of your iPhone.
• Otherwise, your iPhone uses its cellular data connection and communicates that data to your Apple Watch using Bluetooth. Of course, your iPhone must be near your Apple Watch for this to work.

If your Apple Watch isn't connected or paired with your iPhone - Apple Support

That is correct. Wi-Fi is required to pair your Apple Watch to your iPhone.

Set up your Apple Watch - Apple Support