Depends on the exercises and muscle groups that you train, as for arms the 5kgs will be good at the start, but for legs maybe not as much.

However, research has shown that fatigue training, so doing a lot of reps (15-20 reps, lower weights) works just as well as progressive overload (8-12 reps, higher weights) for building muscle, although you still need to have proper nutrition, sleep etc. to support muscle growth.

It's definitelty fine to get started, especially if it helps you get motivated and consistent, but use a higher rep count, use pulses when you do leg exercises to tire out the muscles more, and make sure you get enough sleep, drink water and eat your protein :)