If you are interested in converting EPUB files to PDF, you will first need to go to a site that offers this service. Go to a site like "Bytes" or "ZEN Pages" to find an EPUB conversion service for your use. Once you have found one, sign up for the service by clicking on the link. Enter the email address of the person who will be reading the document that you want converted into PDF. You can either choose a specific file that you want converted, or you can specify which documents you want converted from any file type - text, Word, Excel, etc.
Choose the settings that you want to be used when converting the documents. For example, you can choose a program such as Adobe Acrobat that will be the best PDF reader for the job. Depending on how many documents you are wanting to convert, the program you choose will vary. On the first screen, you will see a box asking what type of document to convert, and it will usually be a word document.
Click "OK." This will start the process of trying to open the document in the best PDF converter that you have, whether that is Windows or Mac. Once the document is opened, you will then see all of the formats that can be selected and converted to PDF.