just start learning react, when i run my code its giving the exact same line and not concatinating the firstname and lastname. it should be AlveraKhan but it gives $ {firstName} $ {lastName} this output enter image description here

function App() {let firstName ="Alvera" let lastName ="Khan" return (<div> <h1> { '$ {firstName} $ {lastName}' } </h1> </div>)}

i omited the inverted comma, but its gives error