Using a hands-free/waist leash can help keep your hands free for when you're doing a lot at once with your dog, especially if they're a pup!
You can use it to prevent unwanted behaviours that happen indoors, instead of letting your pup roam free and it's a great tool to introduce on-leash manners indoors as you focus on rewarding every good step! Hands-free training will make it so your puppy can spend some time focusing their attention on your (which is essential to bond building and leash training) as you reward them for it, all while you're getting to do other things around the house like your laundry, cleaning, and other chores. Why not have your pup join you? You will want to avoid practicing hands-free training in environments that are too distracting or overstimulating for your puppy, as a hand-held regular leash will be a better option for you to more easily guide your pup towards refocusing on you.