How do I choose a dumbbell set?

Typically, dumbbell weights vary with a 5-pound difference between them, so if you do increase your weight, do it safely by going up in small, 5-pound increments. The best indicator to tell if a dumbbell weight is challenging is if you struggle to get the weight up on the last two reps you are doing in a set.

Which dumbbell is best for beginners?

Go for a pair of 10lb (4kg or 5kg) and 20lb (9kg or 10kg) dumbbells if you are beginner. If you want to lose weight and burn fat, you should focus on compound exercises. You shouldn't even bother with bicep curls and the like. Stick to lifts that target multiple muscle groups.