The pivot point of the ship seems off, and movement seems very twitchy
you can use anything that uses raylib and can build for the web. C can do this just fine. Look over the example template. it is written in C and has a makefile for emscripten.
Yeah, anything that can build for web. There are no specific language requirements, just so long as you can get a WASM build out of it.
The theme game was announced today, nn the webpage, discord, and all participants got an email
Please Join the Raylib discord server, there are several people who can help you get a web build working.
We had a poll a while ago to narrow down the choices. The final choice will be made by the organizers.