I am familiar with HubSpot Lists & Workflows for Lead/Contact Segmentation or Scoring.
But... Does HubSpot have a way to filter out "Contact Us" submitted forms before regsistred as "Contacts" in HubSpot or not ? Will it require a third-party solution ?
This depends on how your "Contact us" form is setup. If it's a HubSpot form, then submissions will create new contacts. You can filter your contact index page (Menu > Contacts > Contacts) by clicking "Advanced filters (0)" and searching for "Form submission". Try and find your form, select it and confirm and HubSpot should return all contacts that submitted the form.
This depends on how your "Contact us" form is setup. If it's a HubSpot form, then submissions will create new contacts. You can filter your contact index page (Menu > Contacts > Contacts) by clicking "Advanced filters (0)" and searching for "Form submission". Try and find your form, select it and confirm and HubSpot should return all contacts that submitted the form.