Add value for submit of a form [closed]

Every time someone submits my form I want to add 1 to a value (MySQL). Then I want to include the number of submission in my PDF. Like: submissions: 002 ---> submission of form ---> adding 1 to the value---> submissions: 003 ---> print the number of submissions on the pdf.

<script>          
    // Function to GeneratePdf
    function GeneratePdf() {
        var element = document.getElementById('message');
        var element = document.getElementById('name');
        html2pdf(element);
    }
</script>

source https://stackoverflow.com/questions/70473157/add-value-for-submit-of-a-form