Breastfeeding Questions

I'm a first time mom who plans to breastfeed.
How do you get your baby to stop sucking your breast? I think I saw online that you're supposed to run your ringer along their gum to get them to open their mouth wide enough for you to pull away. Is that accurate? Is there any other ways?
Also, I know you're supposed to switch breasts.
Do you breastfeed for a few minutes on one breast, and then switch the baby to the other?
Or can you breastfeed on one breast for one feeding, and then a few hours later for the next feeding, just use the other breast?
Sorry for all the questions. I just want to make sure I'm as much educated on breastfeeding as I can be before baby makes her appearance.