"Make it into work" is very colloquial. It's often used to imply that getting to work is difficult. I couldn't make it into work because of the icy weather. I've got a doctoro's appointment thuis morning, but I hope to make it into work by 11am.
"What can I get you?" is a common way to offer someone something to eat or drink(usually drink) in a restaurant setting or at a gathering at someone's home.
"Let me sleep on it" means let me think about it at least until tomorrow, give me a little time to consider it.