No rule for this one
No ending or word group predicts the article of Milch. Learn it as a pair and say it out loud: die Milch.
die Milch
It's die Milch. Milch is feminine.
Ich trinke Tee mit Milch.
I drink tea with milk.
No ending or word group predicts the article of Milch. Learn it as a pair and say it out loud: die Milch.