How can I connect webcam to this program?

I have recently learned to write code based on deep learning and Alexnet. I have watched two videos and I started working with Alexnet.

http://youtube.com/watch?v=-ENmRfKWjmo&t=88s

https://www.youtube.com/watch?v=NQjoaptSEoo

I'm training my own images. how can I connect a webcam to the Transfer Learning method When I run the Transfer Learning code? do I need to write a function for webcame? or should I write the main code in the while loop? because in the video MathWorks senior talked about them separately. I am completely confused. could you please guide me?