casual conversation

Can I use this expression when I fail to pay? Is it common? ; Carlos and I are up to our assess in bills.
e.g
A: Carlos and I are up to our ears in bills. 카를로스와 나는 청구서에 치여요.
B : You might want to think about looking for a job. 그럼 직업을 구해 보는게 좋을 겁니다.

Sometimes when Korean moms call their children, can I use it like this; Get your little fannies inside! Is it normal expression? Yes or you can say "Little butts" or "behinds" instead of fannies.
When the kids are punished, can I say like this: take your lumps.
e.g
Mom : Get your little fannies inside! 얼른 집에 들어와!
Uncle : Who you hiding from? 누굴 피해 있는 거야?
You know ?what I say? Go on home, take your lumps. 무슨말인지 알지? 집에가서 떳떳하게 벌을 받으렴.
Kids: We don’t want to get spanked. 엉덩이 맞기 싫어요.

casual conversation

Can I use this expression when I fail to pay? Is it common? (YES) ; Carlos and I are up to our assess in bills.
e.g
A: Carlos and I are up to our asses in bills. 카를로스와 나는 청구서에 치여요.
B : You might want to think about looking for a job. 그럼 직업을 구해 보는게 좋을 겁니다.
This is a natural response when someone is talking about money problems.

Sometimes when Korean moms call their children, can I use it like this; Get your little fannies inside! Is it normal expression?
When the kids are punished, can I say like this: take your lumps.
e.g
Mom : Get your little fannies inside! 얼른 집에 들어와! (kkkkk- Get your little butts inside the house right now; get your little behinds inside)
Uncle : Who you hiding from? 누굴 피해 있는 거야?
You know ?what I say? Go on home, take your lumps. 무슨말인지 알지? 집에가서 떳떳하게 벌을 받으렴.  (You know what?  Go on home, and take your lumps.)
Kids: We don’t want to get spanked. 엉덩이 맞기 싫어요.

You've got to learn to take your lumps. (another way to say)

Nice Job!