Question on affordable wireless cameras before buying

Dear community,

I am setting up a small office and I need to buy a security camera with night mode.

The idea is that the camera triggers an alert to my smartphone in case somebody enters the office at whatever time and that I record these events somewhere outside this office for when I am away.

I couldn’t find the information if the recordings would only be saved on an SD card on the camera itself or if they would be pushed outside to the smartphone app for example for me to be able to access them even in the eventuality the camera also would get stolen in case of someone entering.

I am considering the eufy by Anker 2K Security Camera which gets power through a USB port so I can place a battery bank in the middle acting as a little UPS for the camera, it would be connected over Wifi to a Wireless router with a SIM card that provides unlimited internet, so in case of a power outage the camera and Internet connection should continue running without trouble for some hours.

Thanks a lot for your advice and comments