Welcome to the community, @Kelly_Cammack! :grinning_face_with_big_eyes: There are a couple of ways to pull this off, though they each have their potential drawbacks. Both involve using Airtable’s form-prefilling feature when building the link the user will click on to open the follow-up questions form. Read more about prefilling forms here:
One option is to prefill a link field that links the follow-up question form to the original application. The drawback to this is that there’s no way to prevent the user from removing that link or linking to a completely different application record.
The other way is to prefill a text field with the record ID of the associated application record, and use an automation to link to that application record after submission. You could add a comment in the form field description asking the user to leave the text alone, but as with option 1, there’s no way to prevent the user from deleting the text. (Unfortunately Airtable doesn’t currently support prefilling hidden fields, so the field will need to be visible in order for its contents to be saved.)
A variation on that second option is to use a third-party form tool instead of Airtable. For example, JotForm supports hidden fields and can submit form contents directly to Airtable.