There is no such thing as a female Cat A prison, and never has been. High risk female prisoners are kept in the same closed jails as other female prisoners.
A prisoner like Couzens will go to a dispersal prison, probably to Wakefield initially as they hold a lot of high-profile sex offenders and Cat As. He is likely to be put on constant watch to prevent him committing suicide. This is not because the Prison Service are a bunch of pansies who want to cuddle prisoners, but because suicides create a LOT of paperwork, and also because the decent thing is not to allow people to commit suicide. Also, if one prisoner kills themselves, it can start off a rash of "copycat" suicides and self-harm among more vulnerable prisoners, and noone wants that either.
The person who suggested that he will never see a tree again is fantasising. He will spend many, many years in dispersal prisons, but these prisons have grounds, and gardens. He'll see trees.
Prisoners can get jobs and do education. They earn a bit of money, it varies hugely by prison as to how much they earn. Its not much, but it pays for vapes, phone calls, extra food, snacks, coffee etc. Prison is REALLY BORING.
Most prisoners are locked up 23 hours a day at the moment. They have TVs in cell if their behaviour is good, and a lot of prisons have in-cell phones. These only make outgoing calls, prisoners have their own PIN to make calls, and have to buy phone credits out of their own money. The food is pretty grim, because its so cheap. Prisoners have access to health care like everyone else, and like everyone else, they have to wait ages to be seen.
There is a daily routine, but there is no "bedtime". If they want to stay up all night and watch telly or listen to the radio, that's up.to them, but they're not allowed to disturb their neighbours; if they do, they'll get their cell electrics turned off.
Basically, for anyone who's had a normal life outside, prison is shit.