CSS

image to fill div

.fill {
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden
}
.fill img {
    flex-shrink: 0;
    min-width: 100%;
    min-height: 100%
}

image to fill container size

  background-size: 1000px 300px;
  backdrop-filter: blur(5px);
  background-position: center;
  background-repeat: no-repeat;