I do not know of any easy way to do this. You will have to enter individuals one at a time, establishing the correct relationship between people and entering birth, marriage, death dates and any other facts you know about them. You can also copy/paste the information you have into the notes section of FTM.
I suggest you start with yourself and enter 15 or 20 people. At that point stop and learn to use FTM. Go through the various options and menus and try them out. Don’t worry about making incorrect relationships like marrying your brother to his cousin and switching your sister to a different set of parents. After you a comfortable using FTM you can start over building the real file. Keep the file you learned with. That way if you get into a situation where you are not sure what you are doing you have a place to try it out.