How to protect CODE TAMPERING in Flutter?

I’m new to Flutter and I’m creating an app in Flutter. Currently I’m going through some of the security points. One of which is “Code Tampering”.

How to protect the app from code tampering & code injection? In Native Android, we use to check verify the Release key Signature so that we can avoid code tampering. Is there any plugin or any way to do the same in Flutter? Thanks in advance.