See this 6-week old standard poodle puppy? He is in his first day of crate training. See how he is alert and a little tense but he is not in distress. He is in his "session" mode. He knows he is working and will be supported and encouraged throughout the entire process. With gentleness and consistent commands, this can be learned in one day.
Remember that puppies do not know our language, they must be taught, so use the same words over and over.