I see so many employees that give their 2-week notice and then proceed to slack off for 2 weeks because "fuck it, I'm leaving anyway."
But this is a bad decision.
Think about it. The entire reason why you gave 2 weeks was so you would be leaving on good terms and not burning bridges. You never know where life takes you and it's possible that you may need to apply at your old job again someday.
But by slacking off during your final weeks you are leaving them with their most recent memory of you being one of laziness. This will lower your chances of being rehired there if you ever need to be.
If you don't care about burning bridges and you're 100% certain you'll never return to that company, then just quit and walk out. No need to give 2 week notice.
But it makes no sense to give a 2 week notice then then burn your bridge anyway by being lazy.