Which language or website can I use as a tutorial to create heat maps? I want to customize my own heat map (e.g give it for example a map (such as a house top view) and use heat map on it, not specifically an actual world map)
In javascript you can create heatmap using heatmap.js.
One example is on codepen - this time just js and html canvas - link.
That's what I've found. Good luck!