Then the cloud covered the Tent and the dazzling light of the Lord's presence filled it. 1
References for Exodus 40:34
Because of this, Moses could not go into the Tent.
The Israelites moved their camp to another place only when the cloud lifted from the Tent.
As long as the cloud stayed there, they did not move their camp.
During all their wanderings they could see the cloud of the Lord's presence over the Tent during the day and a fire burning above it during the night.