How to start with my idea?

[bch80]

Hello,

I'd like to create some sort of Single Page Application.
On the first page, there should be only one form field.
The data gets sent to an API or similar (response can be GraphQL).
Then, the API returns data.
The field should slide to the top of the page.
And data should be filled and displayed under the form / field.

I've finished the tutorials and I've implemented the form how to plus, I've looked into Formik.

Should I now create a HTML MVP without functionality first but with the finished design?
Can I use any One Page Love Template or similar or do I best stick to any of the starter kits from Gatsby?