Pronouns are things that replace that noun with her or him, but this is accommodated by the sentence subject.
what i meant is in a sentence when there is an object or person in the sentence is when you are allowed to use a pronoun
Personal Pronoun:-
Now pronoun that changes by the way of sentence example:-
I love cars
we love studying
they can do anything
I, we, they are personal by your sentence
now she is a third perspective while i is a first point of view