To talk to your companions click on their names. To give them food, water, or medicine, click on the buttons underneath the name of the desired recipient. Be careful not to give too much of a resource to an individual, or else the rest of the group might die. However, it may be the case that you can only save one of your companions. If that is the case, then decide quickly, or else everyone might die. Also, don't forget to eat and drink, when you die it is game over.