Install Ubuntu on a Raspberry Pi | Ubuntu
https://ubuntu.com/download/raspberry-piInstall Ubuntu on a Raspberry Pi | Ubuntu Install Ubuntu on a Raspberry Pi Running Ubuntu on your Raspberry Pi is easy. Just pick the OS image you want, flash it onto a microSD card, load it onto your Pi and away you go. First time installing Ubuntu on Raspberry Pi? Follow our desktop, server and core tutorials. Download Ubuntu Desktop
Raspberry Pi OS – Raspberry Pi
https://www.raspberrypi.com/softwareDownload and install Raspberry Pi Imager to a computer with an SD card reader. Put the SD card you'll use with your Raspberry Pi into the reader and run Raspberry Pi Imager. Download for Windows Download for macOS Download for Ubuntu for x86 To install on Raspberry Pi OS, type sudo apt install rpi-imager in a Terminal window.