How can make State City Dropdown List in Laravel,of first step

i have question about this code.why i can save data on table. can you help me step to step for learn create and save state and city in table. THIS CODE SHOW STATE AND STATE'S CITY FOR ME BUT HOW CAN SAVE IT?

BLADE.PHP

<select name="state" onChange="iranwebsv(this.value);">
  <option value="0">select state</option>
  <option value="1">sate1</option>
  <option value="2">STATE2</option>
  <option value="3">STATE3</option>
  option value="4">STATE4</option>
</select>
<select name="city" id="city">
    <option value="0">SELECT CITY</option>
</select>

.JS

 <script>
        function iranwebsv(state)
        {
            with(document.getElementById('city'))
            {
                options.length = 0;

                if(state == 0)
                {
                    options[0] = new Option('SELECT STATE' , '0');
                }

                if(state == 1)
                {
                    options[0] = new Option('SELECT CITY' , '0');
                    options[1] = new Option('احمدآبادمستوفي' , '33131');
                    options[2] = new Option('ادران' , '31541');
                }
                if(state == 2)
                {
                    options[0] = new Option('لوندويل' , '43961');
                    options[1] = new Option('ليسار' , '43761');
                    options[2] = new Option('ماسال' , '4381');
                }
                if(state == 3)
                {
                    options[0] = new Option('SELECT CITY' , '0');
                    options[1] = new Option('ابشاحمد' , '54671');
                    options[2] = new Option('اذغان' , '54561');
                    options[3] = new Option('اسب فروشان' , '54731');
              
                }
                if(state == 4)
                {
                    options[0] = new Option('SELECT CITY' , '0');
                    options[1] = new Option('اروندكنار' , '6331');
                }
            }
        }
    </script>