database"user"..using for loop..i am not able to implement for loop to if statement

for (let i = 0 ; i

{

 if(this.username === user[i].username && this.password === user[i].password){
    this.title="Successfully login your account";
    this.router.navigate(['/home']);

return;
}else{ this.title = "Please check your username and password (or) create New Account in Register";

return; }

}

return user[i];

}