Starting competitive programming
By - Prabhav2003
Practice problems from various coding platforms i.e Hackerrank, Leet Code etc.
We have a very good resource for building solid background in data structures, algorithms and problem solving in general: https://www.thealgorists.com/Algo . Feel free to take a look. The only downside is we do not use C++ . We use Java, and currently working on adding Python.