How to transfer the Firebase web.app to > a 20$ SquareSpace clean www.(...).com ?

Hello, I recently bought a domain from SquareSpace 

How to show my firebase React JS website in my brand new URL ? 🤣
(I anonymized data )
See I have configurated that in the Firebase Side : 

But as off now, I can only see that in my brand new URL : 

Please help me if you know what to do...

Thank you and happy 2024 coding guys

Alex