I'm of the opinion that you can eat as many fruits and vegetables as you want and it shouldn't hurt you. You might not lose weight eating too many fruits, but you'll be a lot healthier.
When I need to lose weight, my go-to is Okra. A bag of frozen okra is, IIRC, about 150 calories and eating 3/4 a bag will have you over-full.
Fruit is high in sugar (fructose). Some fruit, like apples, have low calorie density and high fiber and water content so they are very filling for the calories you consume. Others, like grapes and bananas, have higher calorie density and should be eaten in moderation just like anything else that's full of sugar.
When I need to lose weight, my go-to is Okra. A bag of frozen okra is, IIRC, about 150 calories and eating 3/4 a bag will have you over-full.