Honestly, in 2026 I would not really bother with OpenGL. Just start with WebGPU, it's much nicer. You can use it easily on most modern browsers or better can even use native libraries like Dawn or WGPU.
In light of WebGPU, I respectfully disagree. Because it has us building shader modules, buffers, and pipelines up-front with descriptors, the task of figuring out why something isn't working is often front-loaded. Pair that with its eloquent warnings (in comparison to, like, gl.getProgramParameter(shader, gl. COMPILE_STATUS) ) and the ability to label all your stuff to see it referred to by name in aforementioned warnings text... I'm rambling, but, there's just a lot of helpful stuff in WebGPU that I don't think OpenGL has, that stands to really help newcomers along