Simple .net core function

Looking for someone to create a .NET core function which processes the following API

https://apigw.leasingoptions.co.uk/reporting/doorevents/getdoorevents/01-09-2019/30-09-2019/07DA8E53-74BD-459C-AF94-A037897A51E3

The items there represent events from our door system.

The output should be List, AttendenceItem being a simple class with the following properties:

date (datetime) - a single date
starttime (datetime) - the earliest time present for that date
endtime (datetime) - the latest time present for that date
totalminutes (int) - minutes between starttime and endtime
totalonsite (int)
totaloffsite (int)

Every IN event from the json means the person was onsite, every OUT means the person went offsite. Using these we can calculate how many minutes the user was onsite or offsite for that day. Only process events
where the door is BACK DOOR or FRONT DOOR, the others are internal doors so are irrelevent.

Hope that makes sense, any questions please ask.

Essentially looking for something like this:

private static void()
{
var result = GetAttendence(new WebClient().DownloadString("https://apigw.leasingoptions.co.uk/reporting/doorevents/getdoorevents/01-09-2019/30-09-2019/07DA8E53-74BD-459C-AF94-A037897A51E3"));
}

private static List GetAttendence (string json)
{
//return x
}

Thanks