Install Ubuntu on a Raspberry Pi | Ubuntu
https://ubuntu.com/download/raspberry-piThe Raspberry Pi 2 only supports 32 bits, so that's an easy choice. However the Raspberry Pi 3 and 4 are 64 bit boards. According to the Raspberry Pi foundation, there are limited benefits to using the 64 bit version for the Pi 3 due to the fact that it only supports 1GB of memory; however, with the Pi 4, the 64 bit version should be faster.
Raspberry Pi 4 | Kali Linux Documentation
www.kali.org › docs › armThe Raspberry Pi 4 has a quad core 1.5GHz processor, with 2GB, 4GB or 8GB of RAM, depending on model. Kali Linux runs on a microSD card. By default, the Kali Linux Raspberry Pi 4 image contains the kali-linux-default metapackage similar to most other platforms. If you wish to install extra tools please refer to our metapackages page.