wordpress – Static WP website and web app are in different host with one domain


I don’t know if this is the right place to post this but I am so much in deep confusion right now.

I have a static WP website hosted in Fastcomet with a domain name www.example.com (namecheap) and also a web app made in Laravel hosted in AWS (free tier).

Now what I want to achieve is I want to create a subdomain www.app.example.com that will redirect to my laravel web app. How can I achieve this kind of scenario? Should I add subdomain to Fastcomet or in AWS? and also what is the correct term for this problem so that I can easily search in google for further reference.