Look, these are young people who are obviously relatively healthy and are living in the UK. It's not hard to get basic work in the UK. As Judge Judy would say - "get a job".
Warehouse work, supermarket work even at basic wages will pay £6.50 or £7.50 per hour.If they both knuckle down, get 35 hour jobs that is the better pert of £500 p.w.
They're just used to being useless. Next step is to set up his own window washing business part time at the weekends - then he'll turn over £20 per hour easily. Then get some education.
PE. If you want to help them put these suggestions to them in a letter and enclose a cheque for say £50.00 or a £20 note and say you would like to help more but of course you have your own bills to pay.
Jeez this is some England where two healthy young adults sit on their asses and think that the creator of the universe will look after them if they stand next to a trolley 70 hrs a month.