1. The materials we need and the main steps.

2. Finished and test it.

Product list:

BC547

https://www.utsource.net/sch/BC547

BC548

https://www.utsource.net/sch/BC548

Capacitor

https://www.utsource.net/category/passive-components/capacitors-1.html

Buzzer

https://www.utsource.net/itm/p/8027239.html

Resistor

https://www.utsource.net/category/passive-components/resistors-1.html

More details, pls check the video on Youtube: