Can I use my digital camera Sony Cybershot as a webcam? if yes,how?

did you read your product manual? if it is the still version you can upload still pics but no motion . however i think what you need is the support site

No.

usually using DC as a webcam causes the ccd/cmos sensor and other internal circuitry to heat up. so even if you find 3rd party software to use dc as a webcam, don't use it