Doing great is 很好.
hello how are you doing
hao.
You can say "你今天怎么样?(nǐ jīntiān zěnme yàng?)" to ask "How are you doing today?" in Chinese.
yes
You can say "爷爷,你好吗?" to ask "How are you doing grandpa?" in Chinese.
In simplified mandarin : Pronounced nǐ hǎo ma?
It's "你在干什么."
sahka
Estoy muy bien
To say "you are doing well" in French, you could say vous faites bien! If you know the person well, you could say tu fais bien!
Estoy muy bien
Tu eres magnifico ...or... estupendo