Wouldn't work very well as a phone though. The networks a 2012 phone support no longer exist. 2G and 3G are both fully shut down where I live. Even if you specifically got a 4G phone from 2012 it might not support VoLTE, so you'd be unable to make calls.

As a wifi internet device it would work but I'm not sure that's what OP is going for.

Batteries will be in bad shape.

Can we do 2010s phones with 2020s battery tech and modems please?