Hey @Dorinda
just that I understood it correctly:
You have a calendar and whenever there is a new event added, updated or deleted in this calendar, you want to create an item in a SharePoint List, correct?
I am not sure why you would need a compose, parse json and apply to each for, you should only receive one item per trigger, so there shouldn't be any array you run through and the output of your trigger is already parsed.
My flow looks like this:

The "Start" column in SharePoint is a date time column and I use the dynamic content "Start time with time zone".
My calendar element:

My SharePoint item:

My timezone is UTC+2, the information within my trigger is:
{
[...]
"subject": "Test Event",
"start": "2021-11-12T07:00:00.0000000",
"end": "2021-11-12T07:30:00.0000000",
"startWithTimeZone": "2021-11-12T07:00:00+00:00",
"endWithTimeZone": "2021-11-12T07:30:00+00:00",
[...]
}
What does happen on your side, when you build the flow like this?
Best regards
Marvin
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