Phrasal verbs are used, mostly, in informal conversation. They are a natural way, usually shorter to convey a number of ideas. Are they simple? Unfortunately the answer is "No. Not really." There are so many phrasal verbs that you can find dictionaries specialised only on Phrasal Verbs. Here's a post introducing the topic, if this is the first time you've heard about them.
Today I'd like you to watch this short lesson about using phrasal verbs when speaking. Write down one or two that might come in handy and try using them the next time you have a conversation in English.