Honesty, if someone were to cut their wrists they probably wouldn’t die very quickly, if at all. They’d have to be pretty precise and cut pretty deep, which, is difficult to do since the human brain and body likes to stay away from dying and/or doing extreme damage to oneself. Someone could, however, pass out from blood loss/pain, but it might take a while. Overall though, cutting someone’s wrists isn’t very effective. Therefore, assuming you’re an author doing research for a story or something, I recommend a cooler way of dying for the character that is doing so, like this- the character is watching the Emoji movie while simultaneously playing Fortnite Battle Royal when suddenly a tiger rips through the screen and befriends the character, they go on several adventures together but then one day, while saving a kitten, that loves to play Magic: The Gathering, from a microwave, a portal is opened, because the tiger started dabbing, and the character dies from being sucked in. Have a nice day.