const map = [
    { name: 'jake', grade: 90 },
    { name: 'cake', grade: 80 },
    { name: 'make', grade: 70 },
    { name: 'rake', grade: 90 },
    { name: 'bake', grade: 80 },
    { name: 'sake', grade: 70 },
]

const res = map.sort((a, b) => (a.grade > b.grade) ? 1 : (a.grade == b.grade) ? ((a.name > b.name) ? 1 : -1) : -1)
console.log(res)