A breathing tube is the same as life support in some ways.
When a persons lungs are not able to keep them breathing to live they will be fitted with a breathing tube and a ventilator will be used to help the person breathe so that is a form of life support.
However there's more than just one form of life support that hospitals can use and deploy to keep the person alive in the event of serious injuries, health issues etc.
There are more machines that are used for life support that are more sophisticated and complicated than a simple ventilator.
There are other life support machines that actually take over the heart and other organs which bypasses those organs to allow the person to continue living while they might be able to replace the heart and other organs.
When a persons life support machine is switched off the person is now relying solely on their own body organs and systems to live.
If the person is in bad shape and is not gonna recover then the person will usually die within a few minutes to a few hours of being removed from life support.
The more serious the persons health is when on life support the faster they will usually die.
The life support is very expensive and costs from $1,500.00 per day to as much as $5,000.00 per day.
So if you don't think someone is gonna come out of it and live or the doctor says that the person on life support can only live on the life support then it would be best to have the life support removed.
It can be a very hard decision to make to remove the life support but if the person has no chance of recovery then it's best for the person to just die and rest in peace.
Being on life support is not really living anyway so while it sounds bad to remove life support it actually is the best thing to do in most cases.
I would never want on life support myself after seeing other people on life support that never recovered.
However if you're a pregnant woman in Texas then if you get on life support the Texas law prohibits the removal of life support while a woman is pregnant.