Claiming credits for my US citizen children after I left USA and my residency status for tax purposes has ended

[MM96]

I was considered US resident for tax purposes and I was continually filing my taxes until the end of 2021. After that, I left the US, I have filed The 2021 tax report. Now I am leaving outside the US and my residency have terminated. I have two US citizens children ( seven and eight years old ) and I want to file taxes for them , mostly to receive tax credit for them. Can I do that ? can I still file for them?

[xmasbaby0]

Please explain exactly what you are trying to accomplish.  You say you are not living in the U.S.   Do you have any  U.S. sourced income?   If not, then you have no reason to file a 2023 tax return.  Filing a tax return because your children are citizens would not yield a refund for you or for the children.   

[MM96]

@xmasbaby0 
Thank you for your response.
No I do not have any US income. I do not know if I should anything for my US citizens children. 
If I am not to file anything now, so when should they file on their own? at what age ? and even if they are not obligated to file if their income below the cutoff, would that not result in them getting any child credit?

[xmasbaby0]

If your children have income that meets the filing threshold, they can file tax returns.  They are not going to get child tax credit or any other child-related credits if that is what you are hoping for.  Only the parent who can claim a child as a dependent can get the child-related credits --- if the parent is eligible.