What evidence must be proved in wrong death claim/suit? What is the difference between clami and suit?

Hello.  I am a Maryland barred attorney and practice in this area.   You can assert a "claim" against a party or its insurance carrier without actually filing a lawsuit.   A claim simply refers to the legal rights you have against the other party.   What specific factual evidence you need depends on the type of case --- for instance, if a wrongful death claim arises out of a car accident, you would need to prove the negligence of the other driver and how that resulted in death.   I strongly recommend talking with a licensed attorney in this state about the specifics of your situation.  Keep in mind that there are strict timelines to file a lawsuit.