Can you take him to the library and let him choose a whole range of books? One option is he chooses 10 books, he then reads the first chapter each until he finds one to finish. If you get through all 10, he chooses the least worst one to fully read. Rinse and repeat. It helps if you have a timetable, either a set time to read, so an hour before bed, or an hour a day, doesn't matter when.
A reading log can also help.
If he is into any kind of computer games, they all have spin off books, or handbooks, which might be worth a try. Also, 14 is old enough to start with fantasy or sci fi, often the world building aspects of these genres appeal to teens.
But I have to say that for kids who don't like reading, reading has to be the only option. So no screens, read a book or stare at the wall. As an adult we often do things we don't want to because we know we have to really, or that it will benefit us in the long term. Kids don't think like that, and if a child does not like reading, they are not going to do it, if they have another, more interesting choice.
People often say, oh I got into reading when I discovered Nancy Drew. But no, what really happened was there were only 4 TV channels with very limited children's shows, and you started reading Nancy Drew because there was literally nothing else to do!
Sorry, that is a bit pessimistic, and hopefully other people will come on tell me how wrong I am, because I fear most children growing up in this digital on demand environment are going to end up functionally illiterate.