Questions about maternity leave

I’m a FTM and had a few questions

When do i sign out of work for maternity leave?

I know in my state i get paid maternity leave but is that every week or bi weekly?

How many weeks do i have on maternity leave and does that count if i leave before baby’s born? Ex. If left 2weeks before baby’s born and i only have six does that mean baby’s here i only have 4 weeks left?