"Do you have a pet?"
To answer the question "petto ga imasuka?" (Do you have a pet?) in Japanese, you can respond affirmatively by saying "はい、ペットがいます" (Hai, petto ga imasu) if you have a pet, or negatively with "いいえ、ペットはいません" (Iie, petto wa imasen) if you don't have one. You can also specify what type of pet you have, such as "犬がいます" (Inu ga imasu) for "I have a dog" or "猫がいます" (Neko ga imasu) for "I have a cat."
you are always in my heart.
Anata WA watashi ga imasu. あなたわ私がいます。
You may say 'anata ga sonna ni yoku benkyou suru riyuu ha shitte imasu.'
"kazoku ga nannin imasu ka."~ this means "how many people are in your family?"
It means 'to be hungry.'
Best would be to say 'Anata/kimi ga koishii' (literally: you are so missed) (Anata would be slightly politer than kimi which is casual for 'you'.) There are several other ways to express it when you miss someone in Japanese. You can simply say 'anata ni aitai' (literally: want to see you), or 'anata wo natsukashindeiru' (I miss you), or 'anata ga inakute sabishii' (with you gone I'm lonely).
You're confusing = あなたが混乱しています(Anata ga konran shite imasu)
'I have 3 cats and 2 dogs' would be猫を3匹と犬を2匹飼っています (neko o sanbiki to inu o nihiki katteimasu) in Japanese.
anata ga aishitenai
This doesn't mean anything complete; 'no' is possessive, so it means "Your wonderful ... [insert noun]." For example, "Anata no subarashii yuuki": "Your magnificent courage". The phrase 'Anata ga subarashii desu' would mean "You are wonderful".
this is an incomplete sentence. hey, why are you Kyoko's.....?