Create new document and switch workbench to Part workbench
.
Click Box and Cylinder
 to create solids.
							Click Booleans, then Boolean Operation dialog will be opened at Task tab in Combo View.
							Select a type of operation at [Boolean Operation], Box at [First Shape] and Cylinder at [Second Shape]. Click to execute the boolean operation.
Operation results are shown below.
							
							
							
							Click to finish Boolean Operation dialog.
Note: Executed boolean operation can be canceled. Select the operation result part in model tree and click [Delete] in right click menu to cancel operation.