Pronouns replace nouns, often avoiding repetition.
Subject pronouns (e.g. he and she in English) are subjects of verbs. In French, subject pronouns are immediately or almost immediately followed by their verbs. Also, verbs must have a subject in French, so always use a pronoun if a verb has no noun subject.
Here are the subject pronouns.
Grammar note: Subject pronouns are labelled by the term 'person,' referring to the subject's role in the conversation. 1st person refers to the person or persons speaking (I, we); 2nd person means the person or persons being spoken to; and 3rd person means the persons or things being spoken about (he, she, it, they).
This table contains some important details about the French subject pronouns.
You should memorize these subject pronouns, including how they are spelled and what they mean. They are also always recited in the same order.