I am 2 years out from an ALIF fusion (they went in through my stomach).
My surgery was a Tuesday morning, and I went home Friday afternoon. They had me up and walking with a brace the day after surgery. Go slow, let the nurses help and you will be fine. It wasn't easy to walk, but it is best in the long run.
Before you can leave the hospital they will want you to learn basic movements (NO Bending, Lifting, Twisting), stairs, getting in a car etc. You also have to have digestion happening, which requires at least passing gas.
Things you will want at home are a toilet riser, cane (I had a walker, but only used it for the first day or two), reading materials/tv and someone to help at least the first few days back.