How will I balance work and a new baby?

Not knowing how work and a baby will fit together is a fair thing to fear, because the honest answer is that no one figures it out in advance. You will not solve this on paper before the baby comes. You will find your footing after, a little at a time, like everyone before you. What helps is loosening the picture in your head of doing both perfectly from day one. The early months are not a test you pass or fail. They are a stretch you get through by adjusting. Your capacity will shift, your priorities will sort themselves, and the version of balance you land on will not look like anyone else's. So instead of trying to plan the whole thing, prepare one concrete thing now: talk with your partner or your manager about what the first weeks will actually look like. One real conversation beats a hundred imagined worries. The rest you will learn by living it, and you will.