I never or I am never?

Both are right. To know what you want to say, we need a complete sentence.

CB

Cool BreezeBoth are right. To know what you want to say, we need a complete sentence.CB

okay

I never down because of what you say.
or
I am never down because of what you say.

Choose the second sentence. To learn about the position of words such as never, seldom, always etc. in a sentence, take a look

CB

I guess here it doesn't depend on the position of words. It rather depends on a verb. Because the first one doesn't even have a verb. (in the first part)

So, @manhthieugia95 You need a verb! (here: to be - 'am')

And then the position of 'never':
I am never down, ........
I never do that.
I have never done that.
Never I would do that. / I would never do that.