Getting started with powershell API

I have been trying to find a guide or examples on using invoke-webrequest in powershell to do some simple data gathering. I was unable to find any documentation regarding this. Is there some examples or some documentation on using powershell with sophos central API?

I am quite new to API calls in general.

I started with the example invoke-webrequest on the basic API help page, but I am not sure where to go past that.