live on sth
phrasal verb with live verb uk/lɪv/ us
if you live on an amount of money, that is the money that you use to buy the things that you need:
Nearly 5 million of Morocco's 33 million people live on less than $2 a day, according to the World Bank.
live on a budget/a low income/a fixed income etc. Many retired people living on fixed incomes need to estimate what the purchasing power of money will be over long periods in the future.