Can iPhone cellular data be used to access internet and call on Apple Watch?

I have been using a Series 4 GPS Only Apple Watch for 5 years and 2 months.

The carrier is not involved. For all intents and purposes, the GPS Only Apple Watch is a fancy Bluetooth speaker as far as the carrier is concerned, and they do not know, nor care that you are using it.

And the GPS Only Apple Watch is less expensive than the cellular model, an no monthly charges. So over the past 5 years I saved $100 in the original purchase, and about $620 in carrier $10/month fees.

Because I always have my iPhone nearby, it does EVERYTHING my Wife’s cellular Apple Watch does.

Things I do with my GPS Only Series 4 Apple Watch:

• It tells time, date, day of the week

• Every iPhone alarm, appears on my wrist, where you can acknowledge it, dismiss it, etc…

• I like the iPhone 3rd party “Alarmed” app (http://yoctoville.com), for my alarms

• Ring.com door bell can display a static image on the Apple Watch

• Weather (this gets used a lot)

• MyRadar 3rd party app will display radar image

• MyRadar and WeatherBug 3rd party apps will send you weather alerts

• Make/Receive phone calls

• Make/Receive FaceTime audio calls

• Use Walkie-Talkie

• Silence phone ringing by pressing the digital crown

• Hang up on spam calls

• Send & receive iMessages

• Send & receive SMS TEXT

• Say “Hey Siri, 14 and a half minute timer”

• Say “Hey Siri, remind me when I get home to do xyz”

• Say “Hey Siri, message my wife/husband/Susan/George/etc…”

• Say “Hey Siri, start my Outdoor Walk”

• Say “Hey Siri, end my exercise”

• Use a 3rd party garage door opener app and device (such as MyQ)

• You can check your calendar

• If you need to take an iPhone picture where you cannot see the screen, use Apple Watch Camera app as a view finder/shutter release

• 3rd party Tide app for beach visits

• Hand washing reminder and timer

• Unlock your Mac (I do this several times a day)

• Unlock your iPhone when you are wearing a mask

• Track your exercise and physical activities

Since my Wife got her Apple Watch, we have been able to reliably iMessage each other, as she never keeps here iPhone on her person.

If my Apple Watch was lost, stolen, or broken, I would order a replacement as fast as possible, as I would miss it so much. 

the carrier would not be able to tell the difference with data and voice used by the iphone and what data and voice was used by the iphone on behalf of the watch

sure when the watch have to make calls or access internet data or send and receive sms it just has to be in range of the iphone, when it is then it functions just like the cellular apple watch

and with the cellular data its using from my phone i dont have to pay extra and the apple watch can do all the same features it would if it was connected to wi-fi?

thank you so much