On the 5th day after wisdom teeth extraction, can i resume normal eating/smoking habits?

It should be fine: Unless there's pus, bleeding or swelling. Have fun!

Yes: I advise my patients to avoid smoking for the first two to three days following surgery, and longer if possible to avoid the potential of a dry socket and compromised wound healing. I recommend starting on a soft diet and advancing to a regular diet as they can tolerate it. For some people, that means on the way home from surgery.