I confirmed to my self that just an idea is not enough :)
From technical things, I did my first SFX (more like an attempt) and it was a lot of fun. and now I want to record sounds :D Another important thing I learned is that pre-compiling shaders for web builds is a must for action games, because the lagging during first phases of a game were killing me.
I found the shaders stuttering on the last day, because I create the first web export on the last day, big mistake. Test your release builds sooner, especially web builds.