Can I Sue McDonald's for false advertising about lobby being open 24 hours? which is a lie.

What damages have you suffered as a result? Lawsuits are expensive. It seems a complaint to the manager or a letter to the corporate office would get the problem fixed, although the likely fix would be simply to change the sign on the door, not to open the lobby 24 hours a day. (FYI, not every McDonald's is open 24 hours nor does every McDonald's claim to have its lobby open 24 hours.)

No you have no claim for damages based on this description. False advertising would not support any such claim. as previously stated filing a claim is expensive.

In order to have a claim or to sue, you must present damages. I don't see anything in your post that shows any type of damages whatsoever. Call McDonald's corporate headquarters to complain if you want, but you have nothing to file a lawsuit about here.