Are there anything to care about in this universe? Due to impermanance of everything, Are there anything to be happy or sad about ? Even about dhamma ?

If something seems like to be happy, there are some reasons to not to be happy.


It is impermanant for sure. but also,
That happiness make sadness in the future (future includes next lives) (I need to be sure about this sententce, please mention about this in your answer)


Are enlightened people happy ? Or neither happy nor sad ?
I think Buddhism recommends you focus on what's virtuous and moral instead of on what's feels pleasurable.

For example, lying, killing, stealing -- are all to be avoided -- and that's important.

Conversely, generosity, kindness, keeping your promises -- that's important too.

There is a word -- sukha -- which might be translated "happiness". It's used in contexts like the Sukhavagga.

I suspect it's a happiness conditioned or caused by an absence not by a presence -- for example not happiness because you have something ("a chocolate bar") but happiness because of not having something ("anger", "greed", "remorse").