This library can help you use graqlph to communicate with magento.
npm i magento-graphql-lib
const { BatchGraphql, InitGraphqlConnect, GraphQl } = require("magento-graphql-lib")
InitGraphqlConnect("http://magentoserver")
async function fun() {
//default store code
const rs1 = await BatchGraphql().Querys(SIGN_IN, { email: "test@test.com", password: "123123123" })
console.log(rs1)
//muit store code
const rs2 = await BatchGraphql(["store1","store2"]).Querys(SIGN_IN, { email: "test@test.com", password: "123123123" })
console.log(rs2)
}
fun()