When Federal Judges get hired or Voted in they are in the Job for the rest of their life or until they die or retire and cannot be a judge anymore.
There might come a time when a Federal Judge is not able to be a Judge due to health issues such as dementia or when they get into a nursing home.
And in that case the Judge would not be able to perform the Judges duties so someone else would have to take over for them.
But yes a Judge especially a Federal Court Judge is paid for life because they are never fired or laid off the Job so if you get a Judge In office then they will likely remain as a Judge until they decide to retire or die.
It will be hard to get a Judge to leave the Job because they get paid pretty good and they had to go through a lot of schooling to get to be a Judge.