You don't need anything to learn to sketch from scratch. Just start sketching and keep at it. Think about it, even children can do it. Perseverance is the key. Now if you want to improve, refine your skill, etc, then you may need help. But not to start sketching from scratch.

People use "material" as a crutch sometime. Once I buy the new sneakers then I can start exercising, once I get new laptop then I can start programming, once I get some money, I can start living, etc. You can start anytime you want.

I'm not judging. I do it all the time myself.