I think you're confusing "live feed" with cellular texting of pics.
You could do the live feed thing, would be spendy on many counts. The cellular cams like Covert Code Black are only as good as the cell coverage at your lease with either AT&T or T-Mobile, no others. Mine worked well for me.
M&P-10+AAC Cyclone - Kel-Tec RFB+Griffin Sportsman Ultra Light 300
ATN OTS 336-50mm 9hz Thermal Monocular
ATN NVM14 NV Monocular