Always listen to your dentist for any specific post-care instructions regarding any treatment your receive. Generally speaking, most people are able to return to school or work the same day after getting a root canal. Similarly to a filling you will likely be numb after the  treatment but the numbness will wear off over time. Over the counter pain medication can also be taken to reduce any pain or discomfort. And it is recommended to avoid eating until the numbness is gone to prevent accidentally biting your checks or tongue.