Calculation exercises

There are a lot of books and computer tools to train tactics, openings and endings, but I cant find anything to train calculation.

And by calculation I mean positions where there are several candidate/semiforced sequences and only one is good and the others fail for some reason.

The goal would be not just to find the correct sequence but to calculate all sequences and point out why they fail. That way you get used to calculate different variations.

Do you know any internet site or book with these kind of exercises? They should also be ordered by difficulty, because I really need to start with simple exercises, I´m so bad calculating.

Play in the style of Magnus GOAT Carlsen: use your instinct and trust yourself.

That.s exactly what I´m doing, but it doesn´t work. Amazing, right?