Turn the alerts you want on, and the rest off.
The Notifications tab in Settings decides what we tell you about, and where it reaches you.

Turn each kind of alert on or off, and choose where it reaches you.
Urgent things — a certificate about to lapse, a message needing your approval — reach you as they happen. Everything else can wait for the weekly summary.
Turning an alert off does not stop the thing happening: it still appears in your Inbox. You stop being pinged about it, which is a different thing.