No, 7-Zip is an open-source program and you don't need any password in order to use it. Once you download and install its latest version, launch it, double-click Computer, Documents, or Network to navigate to the files you want to compress, select them and press the Add () icon:
Using the provided window, type a name for the file, select the archive format, compression level, compression method, the size, and the destination directory and press OK:
Also, you will have the possibility to configure the file with a password using the options from the Encryption section. For further details, you can open the user guide of the software by pressing the F1 key or you can contact the developers using the Support page.