sudo apt install fswebcam
lsusb
look for something ike e.g Bus 001 Device 004: ID 32e4:9230 HD USB Camera HD USB Camera
root@raspberrypi:/home/pi# lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
NOW PLUG IN
root@raspberrypi:/home/pi# lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 32e4:9230 HD USB Camera HD USB Camera
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
ls -l /dev/video*
crw-rw---- 1 root video 81, 13 May 15 20:33 /dev/video0
crw-rw---- 1 root video 81, 15 May 15 20:52 /dev/video1
crw-rw---- 1 root video 81, 4 May 15 20:33 /dev/video10
crw-rw---- 1 root video 81, 5 May 15 20:33 /dev/video11
v4l2-ctl --list-devices
fswebcam -d/dev/video1 --no-banner -r 320x240 -S 10 ./image2.jpg