Others have provided links but in short DT is designed to do scene referred edits. The goal is to preserve as best you can the scene lighting. Levels won’t clip data but the UI is using a 0 to 100 scaling of the data. Doing scene referred edits it is best to set exposure in the image or for a portion of the image to expose well the midtones so essentially setting middle grey as your anchor. Then you use something like filmic to map the dynamic range around that point. The added exposure until that point will likely push the data past 100 percent so levels cannot control it. What you are doing with levels I think you would normally do by setting white relative and black relative with filmic to handle dynamic range…If you do use levels be sure to use RGB levels…