If you need to create records in another table, you can use miniExtensions Form to add/edit records AND their linked records. The way to fill out one form that populates separate items across multiple tables is by enabling this specific feature in linked records fields.
Turning this option ON will allow users to create (or edit) linked records within the same form.
Select a linked records field in your form.
Turn ON one of these options
In the legacy form on app.miniextensions.com
This feature is located inside linked fields. To find it, please go to:
Step 2 Form section (or Step 3 Edit & Add Records in the portal).
Click on the linked records field to see its settings.
Go to Adding & Editing Records.
Turn on the option to use a line-item form to be able to edit or add new linked records to that field.
You would need to create another form and connect them together through this option. This form is for the linked table that you can then select after you enable the ability to add/edit records. It will be used to edit or add those new linked records. The form will then take information and put it across separate tables.