How to pump breast milk and store them?

Hi everyone, I'm a first time mom and unsure of how to correctly store the breast milk. Do you put in milk storage bags individually everytime you finish pumping or accumulate it in a bottle for a day and store them? Should I store in the fridge or freezer? Is the breast milk solid once taken out of freezer? and if so, how do I warm it using a bottle warmer? How do I wash my breast pump? Should I wash after every use and then sterilise it? Thank you for your advice. 🌻