Unfortunately, there is no PeaZip package in the default Ubuntu repositories, but there are several ways to install it. Here I will describe the two methods.
PeaZip is a free, Open Source (LGPLv3) archive manager utility for BSD, Linux, macOS and Windows. Cross-platform, desktop-agnostic GUI archive manager.
PeaZip is a free file archiver utility, similar to WinRar, WinZip, and 7-Zip (or File Roller, and Ark on Linux), based on Open Source technologies. Download PeaZip for Windows... · Linux archive manager · Screenshots · Sources
PeaZip file archiver utility works with most common archive types, open and extract 7Z, ACE(*), BZ2, GZ, RAR, TAR, ZIP, ZIPX archives, installers (DEB, RPM), ...
PeaZip is a free and open-source file management tool that works on multiple operating systems, that offers strong encryption and compression features.