Submissions lets you bring to your users the ability to unlock achievements and rank through a form submission that your website administrators can review to accept or reject it.
First of all, you need to configure admin-reviewed submissions on the achievements or ranks of your choice to allow your users request it through a submission form.
After configure an achievement or rank to accept submissions, you have 2 ways to display the submission form:
1) On blocks (shortcodes and widgets) where an achievement or rank can be displayed you will get the option “Show Submissions” to display it.
For shortcodes, there will be the “submissions” attribute that accepts the “yes” or “no” values.
[gamipress_achievement id="123" submissions="yes"]
2) You can place a submission form anywhere, including in-line on any page or post, using the [gamipress_submission] shortcode or block.
Also, you can place a submission form on any sidebar through widgets provided by this add-on.
To manage all submissions you can check this guide to meet where all submissions are registered and how to approve, reject or revoke them.