It is a very difficult question to answer... First analyze if the player is professional or casual, if he is in a tournament, sit, spin or cashgame, check what is the player's skill level and in what limits he is playing, then think about the blind structure, tournament speed, field, if it is satellite and etc ...
Playing MTT of slow structure the player will tend to spend more time in the game, maybe days, unless it is eliminated fast, whereas they can have sit and go games for 1 hour, a little more or a little less, and a spin game can last a few minutes or only seconds, while cashgame games have no time limit, a player should plan to choose a session length that is comfortable for him, and he can interrupt earlier if he has already won, or even lost, enough for a day, being that sometimes we can extend the session a little, to enjoy a good phase, but it is more correct to avoid prolonging it for a long time.