Hi,

Try like following

function clickStoneName(x){
    document.getElementById("in_StoneName").value = x;
    var eF = document.getElementById("in_StoneName");
    eF.focus();
    const event = new KeyboardEvent('keydown', {
      key: 'Enter',
      code: 'Enter',
      which: 13,
      keyCode: 13,
      charCode: 13,
      bubbles: true,
      cancelable: true,
    });
    eF.dispatchEvent(event);
}

Regards