It’s not only normal, it is highly desirable. If he does this when “he sees words on paper,” it means he has gotten the idea that those squiggles on the page stand for words. He hasn’t cracked the code yet, so he just pretends that he has and provides his own translations. Make deals with him. Say “I’ll read you a story and then you read one to me.” Let him choose the book he wants to “read.” And, if you want to get fancy, cut out (or draw, if you’re talented) some pictures that might hang together as a story and ask him to “read” you the story. Tell him that, since he can’t write yet, you’ll write the story down for him so he can read it later. After you have his narrative printed with the pictures, let him read his story to someone else. Sound like fun? You bet it is. And keep reading to him: there is no better foundation for literacy.
Our parenting advice is given as suggestions only. We recommend you also consult your healthcare provider, and urge you to contact them immediately if your question is urgent or about a medical condition.