Here are some words to help you talk about pets.
mon animal - my pet
J'ai un animal. - I have a pet.
un chien - a dog
un chat - a cat
une tortue - a tortoise
un lapin - a rabbit
un oiseau - a bird
un poisson - a fish
un hamster - a hamster
une souris - a mouse
un cheval - a horse
To make a noun plural in French, you usually add –S. So, un chat becomes deux chats – two cats; une tortue becomes trois tortues – three tortoises.
deux chats - two cats
trois tortues - three tortoises
Un oiseau is different. It ends in U and when there's more than one, you add an X to make oiseaux.
It's similar with the plural of animal, which is animaux.
des oiseaux - some birds
Je n'ai pas d'animaux. - I don't have any pets.