Multitasking is vital to life in the modern world (most likely you are reading this article on a separate tab among many in your browser!), therefore it would make sense to learn a way to express simultaneous tasks in Chinese!
Structure
To express that one thing is done whilst doing something else, the word 一边 (yībiān) is used.
subject+一边+verb,+一边+verb
Note that you sometimes see 一边 shortened to 边 as well, which has a less formal feel.
Examples
我 一边 看 电视,一边 吃 东西。
Note that you must be actively doing both actions. That is, they have to be intentional. If you want to say something happened while another thing was happening, it would be better to use "的时候".