(1) Sea fish is halal.
(2) All types of fish are halal and it is lawful to eat them.
(3) If Shark and Stingrey are fish i.e. a fish with this name is available then it is halal. However, if it is not fish then the ruling shall be different.
(4) There is difference among the elder scholars of fiqh regarding the prawn. It is halal as per those who consider it fish and not halal as per those who do not consider it fish. It is better to leave it. However, if someone eats it then he should not be objected. It is not lawful to eat crab. If squid is a fish then it is halal but if it is some other sea animal other than fish then it is not halal.
(5) The companions (Sahaba) served the meat of ambar (cachalot or whale) to the holy Prophet Muhammad (صلى الله عليه وسلم) and he ate it, but it is mentioned nowhere that ambar was a favourite fish meat to the holy Prophet.
(6) It is large sea fish, which is probably called whale in English.
Allah knows Best!
Darul Uloom Deoband