Get a memory trick from a grammar expert to remember the difference between a subject and object.
Fortunately, it's easy! The subject is the person or thing doing something, and the object is having something done to it.
Just remember the sentence I love you.
I is the subject of the sentence. You is the object of the sentence and also the object of my affection. How’s that? You are the object of my affection and the object of my sentence. It’s like a Valentine’s Day card and grammar trick all rolled into one.