creative coding – online

Multilanguage
Codepen – link
Glitch.com – link
Trinket – link (Java – Python – Blocks – html)

Steam
Scratch3 – link microbit wedo et al
MakeCode – makecode.microbit.org
Snap! – snap.berkeley.edu

Javascript
P5.js – link
Node.js – link
openprocessing.org – link