what is object and subject pronoun?

Answer 1

There are different kinds of pronouns, but the personal pronouns which can be used as subjects or predicate nominatives (called the nominative case) are:
I, you, he,she it
we, you, they
The objective case personal pronouns are used as objects, either as objects of the preposition, indirect or direct objects. They are:
me, you, him,her, it
us, you, them

Hence I may say the following:
I gave him the ball. (him is an indirect object, I is the subject)
You gave the pen to me (you is the subject and me is the object of the preposition)

He gave her as a gift to the sultan. (he is subject and her is the direct object)