Delaware is a tax haven in USA, they are moving from Delaware to I guess Gujarat(maybe) for the IPO so they have to compensate for the transition
Secondary means the capital will be used to buy out shares of early investors. Primary means the capital gets infused into the business.
They're a YC portfolio company, YC mandates each company to be registered in the US. Now meesho is planning for an IPO, for which they need to be registered in India. The whole exercise is being done for that. Phonepe also did the same little while ago
Well done Meesho!