There's no need to add your events manually into Event Calendar App. In case you're interested, here's a small write-up detailing the why.
We sync with wherever your events are already. We can currently sync with the following sources:
Google, Apple, Oulook or Exchange. We use a company called Cronofy to do this,
Facebook. We can sync with any Facebook page.
ICS feed. You've probably never heard of this (and I don't blame you!), but it's a way of integrating with pretty much any calendar provider out there. [We have an article detailing how you can find your .ICS url]
The sync page is the first page you will see after registering with Event Calendar App.
Simply choose the method that suits you the best to continue.