Help me with the Database / Data source in this menu app

Hello, everyone.

I am building an application which we can write our own food menu into the app, and others can search it by the merchant name.
Over several days of trial and error, I have tried airtable at first then firebase. But all failed, I only manage to finish the design by now.

I think my approach maybe wrong. So I want to ask for help.
The app let’s everyone can read, and only users can edit. How can I connect to a database like this structure. I made the local table to help explain this function clearer.

Here is the app link.

I personal want Airtable for this app, or do you think Firebase can do it as well ? or better ?

**Also, can some expert explain for me why datasource Airtable ? why database Airtable ?
Because the blocks are different and makes me confuse to way to implement it. **
Thank you in advance.