Create form in wp admin dashboard and save data in custom created db

I want to create form of field text input and file input in WordPress admin dashboard and save the data in custom created table in database.

function certificate_fields() { ?>
    <h2>Fill the details</h2>
    <form method="post" action="options.php">
        Enter your code : <input type="text" name="s_code" placeholder="Enter Code"><br /><br />
        Upload Certificate image : <input type="file" name="s_image"><br /><br />
        <input type="submit" value="Submit Details">
    </form>
<?php }

Please suggest me.