Please recommend fun classroom activities for 3-year-old children.

When the new school year begins, many 3-year-old international children find it difficult to come to school. I am teaching reading, and these children cannot read yet, so I have been given the task of making school 'fun' for them. The problem is, if the children are too nervous or tired to react, I don't know how to play with them in a fun way. Most children just want to lie down on their desks. Especially for 3-year-olds without nap time, it seems too much. Some children don't even respond to me, turning their heads away. In this situation, please recommend games or songs to help children feel happy at school. It doesn't have to be educational, I just want them to feel that school is fun. Thank you.