DB migration from mySQL to postgreSQL

I have two back-ends: connected to flutter app Production back-end: mySQL + Laravel+ Filament New Back-end: postgreSQL+Laravel+Filament We want to migrate crucial data to postgreSQL without breaking. There are 101 tables and both DB used int method. Because MySQL and PostgreSQL schemas don't match, you have to write a custom mapping script to convert data types, match relations, and prevent ID collisions all while keeping our old system running. Plus, you need to test and create the clean production bundle. Project background story : we migrated from mySQL to PostgreSQL six months ago at that time mysql order id migrated till order id: ~13k but new DB never synced [we started order id :20k fast forward today mysql order id is order id :~16k, so this gap of users and orders and other crucial details we need in new postgreSQL. Our main motive is to migrate data as well as to run both back-ends with synchronised orders for a month atleast so that during transition users can update app. Task 2: i need this new back-end as standalone binary file using frankenphp. We are using VPS and developer must have strong DB connection knowledge + DevOps knowledge to run necessary commands on server and handle customers crucial data carefully, without breach. NDA