Forms are a common way to collect information from a user and send it to another source (either a spreadsheet, a PixieBrix database, or somewhere else via an API). In this case, you'll use the Form element, which embeds a form, similar to the Show a modal or sidebar form brick.
Even if you're just displaying data to a user, you still might use a form to create a search or a dropdown field to let the user select what is displayed.
When you add a form element via the three dots, you'll see a new brick appear in the pipeline called Custom Form. Click that brick to see all your options for configuring a form.