It should be a condition of entry that immigrants maintain a 'deposit', which they can draw on to return home, should they become unable to support themselves.
I don't think existing residents, or even just the private sector, should meet the cost of housing for immigrants, or have to act as an education service. Isn't it reasonable to expect of someone who moves to another country, to find out about how such things work beforehand?
Immigration is only good for this country when immigrants are sufficiently productive so that they can live independently. Where this is not possible, the fairest thing for all would be for immigrants who can't live independently to be able to return home using the deposit they paid on entry.