Where you already able to connect it? Otherwise you can connect the cables according to how they are connected to your transformer. See this post 34 for more details. You should be able to use the way Rubueno describes the wiring.
Make a dumb doorbell smart with Shelly 1 - Share your Projects
Making a doorbell smart using a Shelly 1 and Home Assistant
Tatham Oddie – Tatham Oddie
Home Assistant I have a time pattern trigger (Work routine alarm
Shelly One WIFI Switch - Scargill's Tech Blog
Make a dumb doorbell smart with Shelly 1 - Share your Projects
Make a dumb doorbell smart with Shelly 1 - Share your Projects
Home Assistant EDIT: I THINK I've solved the problem by doing as
Make a dumb doorbell smart with Shelly 1 - Share your Projects
Doorbell button > Shelly Uni config - Configuration - Home