The Android 13 beta is no longer just for developers. Google is launching the public beta phase of the next version of its operating system and allowing users to download and install it, provided they have a Pixel smartphone. 
Remember that a beta version can be unstable and inherently incomplete. It is therefore not recommended to install it on your main smartphone.
With Android 13, Google is focusing on security and privacy. For example, Beta 1 adds new permissions for accessing media files, distinguishing between audio, photo and video files.
The user will then be able to give or not give access permission.
Google is also improving Android’s Keystore and KeyMint modules, in charge of managing encryption keys, and offering developers a new API for playing audio content. Android 13 Beta 1 includes features seen in the developer preview, such as the ability to allow applications to access only certain photos from the film or compatibility with the Bluetooth Low Energy (LE) Audio standard.
If Google uses the same timeline as for Android 12, the final version of Android 13 should be available in October.
Source : Google