Your dentist will make it so that while he/she is doing the root canal you have little or no pain. Your dentist does not want to hurt you. They will advise you to let them know if do feel any pain so they can numb the area more to stop any pain you may be having. Do not be scared about this process they will make it as easy a possible for you.
A crown is like a hat for your tooth. There are different types of crowns depending on what you want and what is advise for you by your dentist. They are tooth color so they look just like your teeth unless you get gold or silver by choice.
I have listed a link below that goes though the step by step process of having a root canal. Check it out for more information.