Can you explain to me how and when to use possessive pronoun

Bonjour Tavonga,

Le mien/le tien/le sien/etc = Mine/yours/his/hers/its (French Possessive Pronouns)

The form of the possessive pronoun relates to the English "mine, yours etc "

They do not agree with the owner of the object, but with the object itself.

Access the link above for a more comprehensive explanation.

Bonne continuation,

Jim

It's difficult to answer such broad questions without just referring you to the specific lesson.