What is required to create an online store from scratch in Java?

Question

Java

Good day.
There is a task: to create an online store for a physical auto parts store that does not have its own database, but uses 4 different databases of suppliers with purchase prices. Also, you need to create an application for popular mobile platforms with the functionality of the same online store. Will the choice of Java as the language for writing the core of the site be justified; is it possible to combine 4 different databases into one catalog with price adjustments; whether the mobile application can interact directly with the core and database of the site itself; Are there any ready-made solutions for a similar task, so as not to reinvent the wheel and not be dishonored in front of the "public"?
PS The questions are silly, because I can't even pull on Junior yet.
Thanks in advance!

Answer 1

Will the choice of Java as the language for writing the core of the site be justified?
If you are more comfortable in Java, write in Java.
Yes, it is possible. I have several online auto parts stores in one way or another regularly synchronize their database with supplier databases.
Can. You fasten the rest-interface to the site and pull it from the mobile application.
Nothing with which one would have to fuck more than when developing from scratch.