I agree with Amy's answer, in the comments. They are planning on walking around the room and talking to people, also known as "mingling".

This is interesting. In this situation, I would interpret it as the person wants to "take a lap" of the bar/party. Which would mean moving around and talking to people. Also known as "working the room." In this situation, it would be acceptable for the person to take their drink with them which would explain the bottle of wine in hand. If they were talking about a round of drinks, it would have been more common for them to say "Who's round is it?" "Do we need another round?" "Let's get a round" etc.... Hope this helps

I think they were talking about laptop, meaning that after the bottle of wine it would be perfect time to get working )))

I have not heard it in this context before. Sometimes one might say “take a lap” to mean that they should take a walk or cool down outside before they get angry or worked up.

Probably , in this context it means let’s take a sip.