PT Koki Teknologi Indonesia

Based on my understanding, you want to do the migration(creating schema, table, etc), if that the case you can use GORM. The library has a features for migration and also it support not only postgre, the other relational db like mysql, cockroach db, etc.

But if i may suggest, the best way to setup the table, etc is by doing directly on the database. why? there are other things that you need to concern on creating a table and column, like the index, constraint, composite index, etc. some of this things will be missed by using the migration tool, if not carefully.

I suggest to choose React and ExpressJS, since it is based on the same programming language (Javascript) -more cost efficient and easy to find resources, Django is using python programming language. And talking about scalability it is depends on your application architecture.

Well if you want to be professional developer, i guest you need to choose what platforms that you want to focus on, if you want to focus on mobile, react native or flutter can be the options since it is designed can be deployed on both famous mobile OS. But flutter and react native for mobile development only support 2D not 3D, it is not suitable if you want to build apps for game industry.