We love octopus, squids in all its form.
Usually, I buy them in frozen form from Asian store, they are more reasonable as well as the fact that it is known that freezing them tenderizes them compounded by the fact that they are readily available whenever needed in the freezer
We buy the larger octopus that are cut into strips for grilling ( see serious eats recipe, very simple) but I prefer the flowered ones ( scored) for stir frying in wok as well as cooking as soup in my cataplana. ( just had them last night stir fried with shrimp, snow peas and asparagus etc but had dinner very late almost midnight bec had a late lunch at a sushi place, one order was fried squid) . For frying, my son prefers the baby squids ( short tentacles) dipped in eggs, sweet potato and panko fried in peanut oil but even better, he prefers the ready mixed Korean seafood frying mix when available ( often run out as he took t he last bag to a party last Friday)
One favorite is from my childhood, that would be dried octopus or squid purchased from Asian store, rehydrated, marinaded , then grilled. This is usually served as an appetizer. Remember not to eat too much, eat slowly bec they are chewy but as you chew slowly the flavor becomes enhanced . The Koreans have recipe for frying and grilling that you can try.
Here is a frying mix from amazon but half the price at Asian store
Here are recipes for Korean squid octopus