Do girls gain weight by lifting 15 kg of dumbbells?

It is not a matter of having dumbbells of a certain weight, because you will need different resistance to different exercises due to their different movements and postures. If you are thinking of buying a dumbbell that helps you with all exercises, I would say buy a 2 or 2.5 kg dumbbell. This shouldn't be too much.

If possible, buy this type of dumbbell as you can add or remove weight so that you can change it from 1kg to around 5kg. 

Learn the right way first hire a personal trainer to learn the correct way to do the exercise. Once your nervous pathway is established, weight can be gained.

Weight training is like learning a cycle, you need to learn balance before increasing your cycling speed. Gaining pounds without knowing the right method is an invitation to an unwanted injury you don't want.

For women, I recommend weights from 0.5 to 5 kg. Weights of 0.5 kg are suitable for women who do not have experience with strength training or who have not exercised for a long time. Weights of 5 kg are suitable for women who have experience with strength training or who already exercise occasionally.

Can dumbbells gain weight?

If you use free weights like dumbbells, the progression is very simple just jump to the next weight (usually a 5-pound gain on most dumbbell sets). So if you're currently lifting 100 pounds in a barbell squat, add no more than 10 pounds. When it's time to gain weight.

So, you are thinking of starting with dumbbells. You should think very carefully about getting dumbbells of the right weight. With properly weighted dumbbells, you will train effectively without putting the wrong kind of tension on your muscles. This will help you achieve your training goals more quickly.

Adjustable dumbbells are dumbbells with adjustable weights. You can also choose dumbbell sets. Use adjustable dumbbells if your fitness goal is to build muscle mass or if you plan to do many different exercises during your workout. This is because, in some exercises, you can carry a heavier weight than others. Want to start building muscle right away? Get an adjustable dumbbell set or dumbbell set. Do your first exercises with the same weight. Once you have the correct posture and can do the exercise with ease, you can move on to a higher weight. Have you already done some exercises with the same weight? In this case, it's also a good idea to switch to adjustable dumbbells or a range of different weights. When you can then do the exercises with the correct movement, posture, and level, your muscles will get used to it again and you can gain the weight again.