I have a calendar list on SP Online, add by default it includes several fields that I don't need (Location, Description, category, recurrence, All day event). I would like to remove those unwanted fields. Apparently the "proper" way to edit forms in SP Online is to use the Power Apps feature, however this is not available to calendar lists. I also tried to create a custom form using SP Designer, but that feature was disabled.
So unless there is a workaround, it seems that I am stuck with these unwanted fields if I am using a calendar list. If I use a regular list with a calendar view, then I am unable to use calendar overlays (which is something I really need).