I’m learning using the Commounlounge’s Competitive Programming Course
Others too are free to answer
i would recommend if you can go for Coding Blocks for C++ go for it. Because that way it’ll be easier to have complete and also you’ll have everything completed in few months at-least the basics otherwise searching online and then going for it won’t be as beneficial as needed. the way you are doing is hard way you’ll need to be dependent on somebody in community for doubts.