I installed Couchbase .NET SDK 3.2.2. When we perform any CRUD operation which object I can use to check if the operation is success or not
The 3.x SDK simply throws exceptions if there is an error, success is the lack of an exception. There are a variety of exception types you can catch to handle special cases. The most common is probably DocumentNotFoundException.
Also, I’d strongly recommend upgrading to SDK 3.2.5. There was a memory-leak bug fixed in 3.2.4 related to passing in cancellation tokens.