Badly/Not well

[Mr.Lucky_One]

"I'm badly"
"I'm not well"

If I am ill can I say like this?

[Mr.Lucky_One]

I mean if saying like this sounds natural?

[emsr2d2]

Please don't post a follow-up question after only twenty minutes. You could have edited your original post.

I am not well.
I am sick.
I am ill.
I am unwell.

We do not say "I'm badly" or "I'm bad. You might say "I'm doing badly" if you're already sick and someone asks you how you are but you would have to be very ill to use that.

[Mr.Lucky_One]

Thanks.
What about "I am sickly."
Is it natural?
How often and in which cases do you english-speakers use this word?

[emsr2d2]

Thanks.
What about "I am sickly."
Is it natural?
How often and in which cases do you English ​(no hyphen is required) speakers use this word?

We don't say that. You will see "He/she was a sickly child" but that means that when he/she was a child, he/she was regularly ill.