UK Employee contract - minimum wage

There is a minimum wage for all, it doesn't matter who you are.

https://www.gov.uk/national-minimum-wage-rates

There is a "National Minimum Wage" and a "National Living Wage"; you have to be over 25 to qualify for national living wage; under that age, you get the national minimum wage.  It's actually expressed as an hourly rate and there are some age bands; word of warning - some people come unstuck if the contract is not full time (i.e. a zero hours contract). 

Current hourly rates are:

Apprentice - £3.50
Under 18 - £4.05
18 to 20 - £5.60
21 to 24 - £7.05
25 and over - £7.50

These rates are reviewed annually, next review is April 2018.  I just worked out that assuming a 40-hour week, national living wage is £1,300 p/month; you might want to ask your friend where she got the £1,800 from?

I need work in UK thanks