Phone call integration in my custom CRM

I want to keep zoom calling, calling history, and audio recording in my customized CRM. What are the procedures required to integrate it? Can you provide step-by-step details to make integration easier

We are doing exactly what you want to do.
Check into Zoom Phone Webhooks.
They provide the events plus arguments for each change of state.
Once configured, your target URL is hit for each configured event when they happen.
There is a sticky point in that you cannot provide a unique id - it provides an id to you.
So you must use something else to uniquely associate the actions with the posted events.

Thank you, but could you please tell me what API I need to integrate from Zoom phone in PHP CI3 to get phone calls, call recording, and call history?