Nurseries... who does it work?!

So i know i need to go visit some but how does it actually work putting your child into nursey... i literally have no idea.

I am trying to work out how many days i should go back to work so i suppose for starters if I was to put baby into nursey 3 days a week do I pay for 3 days x 52 weeks or do you not pay when you are away, say on holiday.

Also, how does napping work? My baby is quite hard to get to sleep during the day.

Also, i breastfeed so would i give them milk to give to her?

She’ll be 12/13 months when she starts!

Any help/advice welcome