I can not find any specific answer in your post. Of course Jesus did not mean the literal night, that is not even question here.
The question is - can we do good works today? How is it "night"?
My specific answer was, Jesus was talking about his being a spiritual kind of light, and that he was going to die, leaving his disciples without his light. "Night is coming" means he will no longer be with them, and they will be unable to walk by his light.
Jesus was calling his Disciples to continue in their present ministry while he was still with them. Of course, later Jesus provided for a continuation of their ministry without him. But it would be light form the Holy Spirit, representing him, at that later day. It would be a new phase of ministry.
At present, Jesus was talking about the ministry in which they were going out two by two in preparation for something they did not yet understand, which was his atoning death. They were to bring as much of Israel as possible into conformity with the righteousness of the Law so as to look, by repentance, to their future national salvation.
The Disciples did not fully know yet, what Jesus' imminent salvation was to mean for them. But in the meantime they were to work, bringing Israel into preparation for his Kingdom. They just didn't realize yet that the coming of his Kingdom was not imminent, and would have to be preceded by Jesus' death, ie the "Night," followed by a complete breakdown of the nation, spiritually and morally.
I think at the heart of it all was that Jesus' Gospel called for Israel to conform to the Law via recognition of Jesus' role as the source of this righteousness up until the point where the Law would completely collapse. Israel had been in covenant with God through the Law, and Jesus' prophetic role kept Israel aligned with that covenant, though I doubt this was well understood immediately.
So, the "Day" refers to Jesus' time as the source of righteousness and truth during the remaining time of the Law. The coming "Night" referred to Jesus' death, bringing the era of Law to an end, when the works of the Law ceased to have any value.