I think you should use React or svelte and for the backend use Next.js or sveltkit and as for a database I would think you should use mongo DB and if you want to make it cross platform use flutter or React native it would be easy to use both of these if you know React they are very similar to each other and as for Next.js it is a full stack framework which uses React on the front end and nodejs at the back end good luck making the application.