Answer 1

An Arduino is a microcontroller motherboard. A microcontroller is a simple computer that can run one program at a time, over and over again. It is very easy to use. A Raspberry Pi is a general-purpose computer, usually with a Linux operating system, and the ability to run multiple programs.

https://makezine.com/2015/12/04/admittedly-simplistic-guide-raspberry-pi-vs-arduino/

Answer 2

arduino is typically a board build around a microcontroller ....while raspberry pi is a credit card sized mini-computer......what you can do with a raspberry pi...is a whole paralysing list..am fairly new to this ..still learning.