You should know how to do it before you start to do it for money, I guess that it what he meant... Family and friends might pay you for trying but if you do something for a stranger, he expects you to know your stuff so if he wants something, he gets it.
Design your homepage first, that you can show to your possible future clients. Then do some basic designs so you can show them what you can do.
It's not easy route if you're a newbie in coding but if you know some of it and are interested, it's great way to make money. Now and in future. I have couple friends who made nearly ten grands in one summer by just doing some websites, they are very good at it though
I learned my basic skills of HTML and CSS from W3Schools, they have good info IMO
you can make so much money off that. probably not worth it if you got caught though.
at 16 most places will hire you (at least here in the US). 16 is the standard for most places to hire. just apply everywhere you can, to be honest. eventually you will land a job somewhere.