You will be able to find the notifications page as the second page in the left navigation menu in Catenda Hub.

On the notifications page you will find all notifications that have been delivered to you from all projects.

On the left of the notifications page you will see your latest notifications and on the right you will be able to filter these notifications.

By default you see 10 notifications per page.
If you want to increase this amount you can change the number after limit= in the URL.

Note that it might take longer for the page to load with more notifications.

If you have email notifications turned on these notifications will also be sent to you either in a summary email or as a separate email per notification.
This can be configured in email notification settings.
If you are not getting emails please check this article.

You will be able to find notification settings as a sub page to the notification page.