How can I directly add an ics file event from email to my calendar in iPhone?

I am following instructions which do not work. I save the ics event from my protonmail to my documents folder in my phone. There is no option to share with my calendar, even when I hold down. It only suggests sharing with apps that are not relevant to my calendar.

The instructions from Apple say I should see a 'share with Calendar' but I've been looking for awhile and there is no option. I am forced to copy paste all theses events, with zoom links and other info, and manually enter them every time. Seems cumbersome.

What am I doing wrong? I can't figure this out in settings, and the topic in here is not very active so I'm on my own. AI says I need a 3rd party app, but that seems absurd when I am already in the Apple system on iCalendar. Help! Please.