Your little Sulcata is at the start of the journey that will lead to him weighing 100lb plus in just a few years. You can expect him to live 50-100 years.
It's important that you raise him well, especially in the early years, to ensure good health.
Have you read the care sheets for Sulcatas? The TFO ones are right up to date unlike the information from pet stores and the internet and, sadly, from some breeders and vets too.
Hello and Welcome. I see you live in a cold wintery state like I do. It will be a few years, 3-5 most likely, but I would be sure you have the room and means to provide a insulated heated shed for him for those cold snow days when he is too large to live in a place smaller then a room. Around 8-10 inches or so.