Not very. One of many reasons I moved!
However, OUH have 950 accommodation units to rent at 20% below market price. Quick check shows a basic room rental of £477 a month, from a minimum net salary of £1585 ..... leaves £250+ a week to live on. Not great but not poverty & food banks either...... but NHS pay is a whole new topic!
Why do people have "no choice but to work zero hours"?
On the nurses for full balance:
https://fullfact.org/economy/how-many-nurses-are-using-foodbanks/
On the last question, because that is the only type of job they can get for any myriad reasons (education, caring for family members as well, limited job opportunities in an area etc etc).