I want to filter one dropdown list depending on another dropdown

I have departments on one side and employees on another side. I want to filter employees depending on the selection of departments. I am not good in javascipt or ajax.

            <div class="pure-checkbox ml-15">
               <input id="checkbox2" name="stars" type="radio" data-type="round" class="checkbox look-me" value="2">
               <label for="checkbox2"> Department </label>
            </div>
            <div id="show-me-three">
               <select class="form-control e1">
                   <option>Select</option>
               @foreach($department as $departments)
                       <option></option>
                   @endforeach
               </select>

            <div class="pure-checkbox ml-15 asset-employee-checkbox">
               <input id="checkbox6" name="stars" type="checkbox" data-type="round" class="checkbox" value="6">
               <label for="checkbox6">Employee</label>
            </div>
            <div class="asset-employee-list-show">
               <select class="form-control e1" name="ename">
                   <option>Select</option>
                       @foreach($all as $alls)
                           <option></option>
                       @endforeach
               </select>
            </div>
            </div>

via Chebli Mohamed