You can connect a webcam to the neo however how useful it will be is questionable. What are your plans for the webcam?
thank you for your responding, I want to make a robot car with web camera , PIR , Ultrasonic and control it with android app by wireless. the camera will be live broadcast .......
It's going to be a challenge to efficiently use the wireless bandwidth to send a live camera feed and control the car. You would need to prioritise the car controlling traffic over camera data to make this work. I suggest you first test how much CPU is consumed by a live camera feed. You can you do this can creating a rtp stream from your usb camera to view on a android app. For the linux side (Neo) you can use VLC (see this link as a starting point, can you do it from the command line) and for android client see this link.
As a followup to that, would it be possible to capture images from the USB camera and run image recognition using an offline library like Tensorflow?