I have recently got into cp and solved a few problems and I find that I can consistently solve Div.2 A problems quite easily. It is actually the B problems that make me think. Although I am usually able to solve them, it generally takes a LOT of time and thinking. So I want to know how and what should I practice and learn to solve the B problems consistently ? Thanks in advance.

I have recently gotten into competitive programming and solved a few problems. But I am looking for a structured way to learn about the data structures and algorithms in cp. So I want to know what algorithms and data structures should I get started with as a beginner and what are the best places to learn about them. Any suggestion would be really helpful. Thanks in advance.

My submission for a problem has been in queue for about 20 minutes now. I am quite new to codeforces. I have never seen this happen before. Is it normal ?