You maybe better off to ask this in Tropical plant forum.
Its normal for some leaves fall off trunk plant if growing young plant. White ooze I don't have clue.

Please post a photo, so we can see what is the issue.

Also where do you live, do you know what variety of coffee it is, etc.

I live in Guatemala, producer of the finest coffee in the world; I have a lot of friends who are coffee growers and will know in a minute what is the problem.

I have 4 tropical gardens for which I have responsibility and every one has coffee trees; they are beautiful and really quite easy to care for.

Probably spidermites or mealybugs. Try and get a bottle of "Safers soap". That stuff is pretty good, and isnt extremely toxic to us (its basically oilly dish soap)

Again, a pic will help. ID also stop watering it everyday. Once a week is good