My 18-month-old son, who is very active and social, likes to eat only when we allow him to watch rhymes. Even though he is super hungry, he refuses to eat (even his favorite food) without watching rhymes.
How can I make him eat without screen time?
It sounds like your son has developed quite a bad habit there. Eating in front of the television is not good, so I think you'll want to nip this habit in the bud straight away. It might seem harsh, but I really think you should simply wait it out. Don't turn on the TV, no matter what. He'll eat when he gets hungry enough.
Don't make a big fuss, and don't engage the child in an argument. Simply tell the child that the television is not going on. The rest is up to him.
Also you may want to generally look at how much screen time the child has, and gradually try to reduce it. Less is definitely more in regards to screen time.
Put the TV away for a couple of weeks. Tell him it is broken. Show him the space where it was to prove to him it has gone. If you convince him the TV is no longer an option hell accept the situation more readily.