When someone is sentenced to death in court they will be taken back to jail for a few weeks or a month until they can be transported to the prison where they will reside until they are executed.
After they are sent to the prison and admitted into the prison the inmate could live there in prison on death row without being able to go outside for 23 hours per day and be a in a maximum security prison and prison cell.
A death row inmate usually gets very little exercise and only around 1 hour per day outside in a cage.
The death row inmate could be in prison for 10 to 20 years and sometimes as long as 30 years before the execution takes place.
The inmate on death row can appeal the execution for years at least a few times and then if the appeals are exhausted the inmate will eventually be executed.
Some inmates are executed 10 years after being sentenced while other inmates may not be executed until 15 or 20 years.
Take Dylan Roof for example he's on death row and will likely be on death row for at least 10 to 15 years before he's actually executed.
Eventually Dylan Roof will be executed but likely not for awhile year.