Variables can be organized into several sections in the spreadsheet view.
The first section is always the Input section, this is not able to be renamed or deleted. Any variables that are in this section will show up in the Dashboard, and are able to be played with (i.e. adjusted) by viewers. If you don't want a variable to appear as an adjustable input, move it out of your model's Inputs section. Note: Model inputs can be in any section of a model!
By default, there are two more sections auto-created when you start a new model, Calculations and Outputs. However, you can delete or rename these, add more sections, and reorder sections as you wish.