Thanks for the answer. If I understand you well, this does not (entirely) meet my needs. The datagrid (showing days) in this option is (or should then be) a list of all available days (...); which is not what I'd like to have.
We have fixed this issue in another way, and I explain it here (perhaps someone also wants to use it) - I have created the Day Entity related to notifications - In my page I have a dataview (entity is Day) and in here, the DateTime attribute Day is visible as a field - On change of this date (and onclick of the "previous" and "next" microflow button a microflow is called - the microflow loads the notification of the chosen date - This is done with a reference set selector with entity-path: Day_Notification/Notification to only show notifications of this day.
Works fine for me :-)
The first problem is easily solved with the Search functionality, just put in the Created Date. Do note that you can set default values for search fields, not sure if you can use CurrentDateTime in these though.
For the paging based on days, you could use a datagrid showing Days (entity), with a listening dataview showing that specific Day. In the dataview you can then show a Datagrid with Notifications constrained to the referenceset with the CurrentObject (Day).