Currently Episerver provides Change Log, for changes made in Content(published, deleted, moved...). There should also be out of the box Change Log for monitoring content Access Rights changes and other Admin Changes.
https://swapcode.wordpress.com/2020/07/06/episerver-activity-log-with-custom-content-security-activity/ this will allow you to configure the change log admin tool so that it logs access rights changes it could be extended in the same principle for other events
Neha, the blog post linked by Scott (thanks ;-) ) is the first version but I've created a NuGet package out of the feature, here is the 'announcement' blog post.
And direct link to the NuGet package in Episerver NuGet Feed: Swapcode.Episerver.AuditLog