These are very important and irregular verbs.
être = to be
avoir = to have
It is important to learn their conjugation perfectly. So listen and repeat several times.
Verbe être
Je suis, Tu es, Il/Elle/On est, Nous sommes, Vous êtes, Ils/Elles sont
Verbe avoir
J’ai, Tu as, Il/Elle/On a, Nous avons, Vous avez, Ils/Elles ont.
Here are a few exercises to get used to these verbs.