I think you can look at problemset and find out which types of problems usually exist in div2 contests. But as you said it is often implementation, greedy, maths, constructive, brute force, strings, sometimes graphs.

Sometimes dp

In my opinion in C,D,E you can expect a lot of stuff since it already overlaps with Div1. But for strictly Div2 problems — A,B, they usually emphasize on coming up with some simple but clever idea or being able to quickly implement an annoying algorithm. They usually don't require a lot of coding and often don't have some well-known algorithm in them, hence the "implementation,sorting,greedy" tags.

When I was starting in Codeforces at first, I found out that the best way to be better at Div2 problems is to solve Div2 problems. I see you've done only one official competition so there are still 200+ competitions waiting for you. You can virtually participate and try to get the A,B right in the time limit, or simply practice (though I prefer virtual participation).

When I first joined Codeforces I would do tons of virtual competitions and that quickly improves your skill of solving those A,B problems. Good luck :)