The behaviour of a text box control on screen, as regards the wrapping of text, is governed by the depth of the control. If its depth only allows one line of text then the text will not wrap. If the depth is sufficient to allow more than one line, then the text will wrap within the horizontal confines of the control, and you'll be able to scroll down to view additional text.
Note that the EnterKeyBehavior property determines whether pressing the enter key when inserting text moves to a new line or exits the control. It does not affect the wrapping of text where an unbroken paragraph will not fit within the horizontal confines of the control. If this property is not set to 'New Line in Field' in a text box control's properties sheet, to enter a new line you should press Ctrl+Enter. The data type of the property's value is Boolean, so in code it should be set to True or False.
BTW the CanGrow property of a text box control in a form does not cause the depth of the control to increase on screen if the text is too long to fit on a singe line. This sometimes confuses people. The property's value being True only takes effect if a form is printed, or if the control is in a report.