Try putting this code on top of your main file, and adjust the MyTitle, icon.ico and 1024 768
from pandac.PandaModules import *
# need to be before the Direct Start Import
loadPrcFileData("", "window-title MyTitle")
loadPrcFileData("", "icon-filename icon.ico")
loadPrcFileData("", "win-size 1024 768")
import direct.directbase.DirectStart