*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
div{
    width: 100%;
    height: 100vh;
    position: relative;
    background: url(a.jpg);
    background-size: cover;
    background-position: center;
}
div:before{
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url(test.png);
    background-size: cover;
    background-position: center;
    mix-blend-mode: screen;
}