This is a simple demo with the ATmega4809 Curiosity Nano development board, but can easily be ported to other devices.
The demo consists of a the board and a common anode 7-segment LED plus current limiting resistors. All of this can easily fit on a protoboard.
The example code shows how to perform timed events without using delay() and how to use FLASH (program memory) to store patterns that never change. This saves RAM space.