ANSWER: 

It is permissible for a man to work there if there’s no other job that you would get where there is no free mixing, as you’re the bread earner.

However you should always lower your gaze and not talk to females unnecessarily and never be alone with a woman in a room. 

Is it permissible for me to work somewhere in school or other sector where co-education(both boys and girls combined) is very normal. Or what should I do?

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