Wireshark
Also on WindowsCaptures and inspects network traffic.
Installs from Ubuntu's own software archive.
Good news: Wireshark runs on Linux. It's the same app you use on Windows, and TuxPick installs it for you from Ubuntu's own software archive.
Install Wireshark with TuxPickIt works on Ubuntu 22.04 and 24.04, and on systems built on them like Zorin OS and Pop!_OS.