Actually Extramarks runs on to platforms
1.First one is gotoschool.extramarks.com which basically provides the schools to run their online classes this platforms depends on the school providing education through it. So we cann’t judge on it.
2.Second one’s content is provided by ectramarks itself only. As per my experience and opinion which I had go through I realise that it needs a lot of improvement in its content as it shows modules just like slide shows whose standard is muc much lower than NCERT books. And its faculties are too much boring and not much intrectable.
So at the last I would like to review that there are many more educational platforms with good and quality content as compare to it and if you would like tjan you go for them.