24MP 1296P HD Trail Camera with WiFi, 5 Million Sensor Outdoor Wildlife Monitoring Waterproof Night Infrared Vision Hunting Camera

SKU: KF35.007

A
It does not need an existing WIFI network. The Unit itself generates its own "hotspot" to connect to your phone wirelessly - functions similar to connecting via bluetooth, but uses WIFI instead to be able to download photos faster. 
A
Theoretically yes you could extend the wifi, get a wifi extender unit, setup wifi with same wifi info as from camera. Connect wifi unit to camera then connect phone to wifi. Extended! Basic Setup info and it’s not for someone who doesn’t know what they are doing. Do your research first before just attempting. 
A
Download the APP in your mobile phone and then connect with WIFI. You can adjust setting and check the photo /video on the phone directly. T75 game camera is Not a webcam, remote control has range limits. 
A
It's connect with phone WiFi, not the router, it has a WiFi remote control for this trail camera, you can use it to turn on/off the game camera WiFi.