How to design a backed end of a website

Question

How to design a backed end development of a website to be able to be adding a post and also to be able to edit your site without not going to your main code like how someone post on Facebook

Answer 1

There are couple of backend flavours.
1. Python - django framework
2. PHP - Laravel framework
3. JavaScript - NodeJS

With JavaScript "CRUD", that's Create, Read, Update and Delete can easily be done with just the front-end. For simple projects, "SPAs", that's Single Page Apps can be employed to accomplish CRUD with popular JS frameworks:
1. Angular
2. Vue (my Favourite)
3. React

And for quite large projects Node JS Express framework handles very well and easily and can integrate MongoDB.