You can first choose which cells you don’t want to be protected (to be user-editable) by setting the Locked status of them to False:
Worksheets("Sheet1").Range("B2:C3").Locked = False
Then, you can protect the sheet, and all the other cells will be protected.
The code to do this, and still allow your VBA code to modify the cells is:
Worksheets("Sheet1").Protect UserInterfaceOnly:=True
or
Call Worksheets("Sheet1").Protect(UserInterfaceOnly:=True)