('), also known as the apostrophe, can be used to bring words together. An example is the word <em>don't.</em> The ' is used to combine the two words <em>do</em> and <em>not</em>. It can also be used to state something as a possession. (Example: That is Sally's food.)
For ("), aka quotation mark, is used to separate the name of something from the rest of the sentence. Like if you're saying the name of a book, you use quotation marks to separate it. (Example: I read this book called "Blue Whales are Cool.) Another way " can be used is for when a character is talking. (Another Example: "Delicious!" Said Samantha.
To summarize, the difference between ' and " is that " is used for character dialogue and to name things. ' is for showing possession and bringing together words.