Can We delete the database pariticipating in AG ?

You cannot delete the database which participating in AG . If you try to delete the database then you will get the error like -

The operation cannot be performed on database "DB Name" because it is involved in a database mirroring session or an availability group

For more details about errors

TITLE: Microsoft SQL Server Management Studio
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Alter failed for Database 'DBNAME'.  (Microsoft.SqlServer.Smo)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=12.0.5000.0+((SQL14_PCU_main).160617-1804)&EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.FailedOperationExceptionText&EvtID=Alter+Database&LinkId=20476

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ADDITIONAL INFORMATION:

An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)

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The operation cannot be performed on database "DB Name" because it is involved in a database mirroring session or an availability group. Some operations are not allowed on a database that is participating in a database mirroring session or in an availability group.
ALTER DATABASE statement failed. (Microsoft SQL Server, Error: 1468)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft%20SQL%20Server&ProdVer=12.00.5000&EvtSrc=MSSQLServer&EvtID=1468&LinkId=20476

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BUTTONS:

OK
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