My question is not easy to explain for myself, but I will train.
I can insert a record into a table´s column form a form with php to mysql without problems. This insert generates an auto_increment record in another column from the same table.
So I want to select this new auto_increment record and insert it in another table. 
<?php
            // process form`enter code here`
            $db_host="myhost";
            $db_user="myuser";
            $db_password="mypassword";
            $db_name="mydbname";
            $db_table_name="table1";
            $db_table_name2="table2";
            $record1= utf8_decode($_POST['record1']);
            $record2= utf8_decode($_POST['redord2']);
            $db_connection = mysqli_connect($db_host,$db_user,$db_password,$db_name);
            if (!$db_connection) {
                die('Could not connect to the database');
            }
            //insert record1 into table1
            $insert_value = 'INSERT INTO `' . $db_name . '`.`'.$db_table_name.'` (`name`) VALUES ("' . $record1 . '")';
            $result1 = $db_connection->query($insert_value);
            //consult auto_increment column from table1
            $select_value = 'SELECT column FROM table1 WHERE name = "' . $record1 . '"';
           //insert record2 into table2 in a row where a column is like $record1 
            $insert_value2 = 'INSERT INTO `' . $db_name . '`.`'.$db_table_name2.'` (`column1, column2`) VALUES ("' . $record2. '","' . $select_value  . '") WHERE name = "'.$db_table_name2.'"';
            $result2 = $db_connection->query($select_value);
            mysqli_close($db_connection);
        ?>
 
     
     
    