

The only solution is that you should practice more and more.
You can go through the following link for clearing concepts of tigonometry of class 10.
https://www.youtube.com/watch?v=Fkco1UvUg7k
If you still face problems, then you can study trigonometry of higher class like class 11, so that after practicing high level of questions you are able to solve questions of class 10. For that, you can refer to the following link.
https://www.youtube.com/playlist?list=PLCzaIJYXP5YfJbWwJCFw0jKFp-BWHY4Jo
