1. Materials we need.
2. Screenshot of some steps.
3. Finished and test.
Product list:
dtmf module https://www.utsource.net/itm/p/8673747.html
relay https://www.utsource.net/itm/p/8673177.html
jumpers wire https://www.utsource.net/itm/p/7961311.html
More details, you can check the video on Youtube: