Were people in the dessert happy or sad? I mean did they have a happy life and joy or it was suffering?

Shalom, Thank you for your question. It is a little hard to answer, as there are no direct teachings as to the joy or suffering of the Jews in the 40 years in the dessert. However, it would fair to say that there were periods of immense joy, and times of great suffering and struggle. What could be more joyous than singing the Song at the Sea after the sea had parted and the Jewish people saved? What could be greater than standing at Mount Sinai and receiving the Torah from G-d? On the other hand – we read of times when the Jewish people complained bitterly to Moses. There were times of G-dly punishment, when many were killed. In fact, after the sin of the spies, and the people rejecting the Land of Israel, the whole Jewish people were punished with a decree of death in the wilderness. This must have been a terrible time. So, in answer to your question – both. Blessings.