how do i display all item from my local storage when key is unknown

Question

html form where email is taken as key. rest all input is stored in local storage key values

i want to display on the firstname and last name in a table

{
        let user={
            FirstName: document.getElementById("formReg").Firstname.value,
            LastName: document.getElementById("formReg").Surname.value,
            pass1: document.getElementById("formReg").pswd.value,
            email: document.getElementById("formReg").email.value,
            dateofbirth: document.getElementById("formReg").birthday.value,
            score:0,
        };

        alert(JSON.stringify(user));
        localStorage.setItem(user.email,JSON.stringify(user));