The Shulchan Aruch OC 639:2 answers your question
We eat and drink and sleep in the Sukkah all seven days, both day and
night, and we do not sleep outside of the Sukkah, even a very short
sleep. But one may eat an insubstantial meal outside of the Sukkah.
And how much is an insubstantial meal? Approximately an egg's worth of
a loaf of bread. And it is permitted to drink water and wine and eat
fruit even if he made it his meal (own opinion) outside of the Sukkah.
And he who is stringent upon himself, and will not drink even water
outside of the Sukkah, he is praised. And a dish made of the five
species [of grain], if he makes it his meal, it considered a proper
meal and requires a Sukkah.
According to the letter of the law one is only required to eat in the
Sukkah if he is eating more than a Kibeitza of bread or Mezonos
[within [the time limit of] Kdei Achilas Pras]. All foods which do not carry the blessing
of Mezonos or Hamotzi may be eaten outside the Sukkah without limit,
even if one sets a meal over those foods. However one who is stringent
to eat also these foods in the Sukkah, is praised.
There is some dispute whether non-hamotzi/mezonot products can be eaten outside a sukkah when they compose a full meal. For this reason, as well as to discuss whether it is appropriate to go to such a hotel, and whether one should travel to look for a sukkah, it is best to ask a rabbi who knows you (see also the end of here).