Apple watch cellular for dementia tracker

Hi

So I am thinking of getting an Apple Watch 7 as a dementia tracker. I am thinking this has the added fall detection and the health trackers. Sounds perfect but do I also need an iPhone for him?...

He had an I phone, it was toooo complicated, so now has an easy phone.

If I use my phone to set it up (I assume you need an Iphone to set it up) Then have an activated sim in the watch, will it do what I need??

I need to track the watch without the wearer owning an iPhone..

Any help would be great, thank you : )