How to get clothing (buckled belt)?

The sewing studio provides both the sewing tools and sewing kit. You need to go through all the levels of the tools to create a sewing machine. Tapping on that converts the thread and cloth to items and the belt is the fourth level item

Use the sewing drawer and merge to the highest level to get the sewing machine. Also merge little blue bags from sewing drawer to highest level to get cloth and thread then tap on the sewing machine and it will give different clothing articles.