Does warranty of newly brought laptop disappeared after factory reset?

No, Guarantee depends on machine sequential. Number, and from buy receipt date. A guarantee is given by producers on the equipment like motherboard, processor, slam, wifi card and so on. For Windows, they will help, however, you can likewise take help of Microsoft client assistance. 

It is better before doing a reset, register windows and ms office utilizing Microsoft account in the setting. At the point when you again introduce Windows, you can undoubtedly start utilizing sign-in into Microsoft account.