For how much to tackle lesson-wise each day, you shouldn't push trying to go too fast. First, your finger tips will hurt until you build up callouses, then your fingers will not cooperate with your brain until you get strength and coordination and muscle memory. These are the big hurdles in the beginning. I personally preferred beginning with an electric guitar because the string gage is smaller than acoustic and easier on the fingers. Some people argue that starting on acoustic is better because it builds more finger strength...but some people can get discouraged by the difficulty at first.
Go to the core learning system and start with guitar level 1 fundamentals and slowly work you way from there. It is easier having a music background so you can probably skip all the parts that cover whole note, half notes, etc. Find some easy songs that you can start learning. Break it down measure by measure. It may take a beginner a few weeks to play through a simple song at half speed. Speed comes with practice and experience so don't force going faster.