La fonction de suggestion automatique permet d'affiner rapidement votre recherche en suggérant des correspondances possibles au fur et à mesure de la frappe.
Can you give me more details on what you're looking to accomplish? I'm not sure I understand the goal you're describing, so it's tough to give technical recommendations.
That submission id is only used internally, and therefore only appears in the query parameter you highlighted in that screenshot. If you need to collect it, you can pull it from the URL of your thank you page using Javascript.