The first photo looks normal, just a few dying leaves at the bottom. The second photo sows an aborted squash with mold growing ion it. That should be removed and discarded in trash to prevent release of spores. All in all appears to be looking good. Dark green color of base stem is normal. Abortion is normal as the plant will only support development of fruits as it has the energy to do so, lack of pollination also leads to abortion, but since you are showing a developing squash on the plant probably not the immediate cause.
