An updated experience for alerts on Azure is coming (currently in preview).
If you want to enable the new experience, access your Azure portal and reach the Monitor\Alerts blade, then click on the purple banner to enable it
The new experience is providing better insight on alerts and what is happening on your Azure tenant/resources by grouping by severity (the well known severity level 0 (critical) to 4)
You can roll back to the previous experience (at least until the experience is GA) by clicking again on the blue banner.
If there is any alert, you can click on it to get more details and history
Also similar alerts will be automatically group, using machine learning, to reduce the noise