Advices about website's architecture and how to deal with docker containers

I want to start working on a project but I don't know if it's possible (I guess so), I want to implement 3 versions of backend and frontend each in a different language like in the picture below. I want to dockerize each of the "version". So far so good.

Basic Architecture

I wonder what is the best solution ; is it to run all containers and map each container on different port and switch between them when clicking on a button like "switch to angular" ?

Or a solution, that everytime I clicked on a button like "switch to react", then it start the container that runs react app and stop the old one. I guess this one is more efficient because there is only two containers running (backend and frontend) but I'm not sure if it's possible to start a container from just clicking on a button.

Second question is how I deal with X containers to choose which one to run ?

Where I could deploy that kind of appication ? Any PaaS or anything else to advice ?

If you have any other advices to provide, I'll take them with pleasure

Note : The project have absolutley 0 interest, it's only training and discover technologies.