Hii Hilmi Faliha..

If are preparing for NEET strictly stick to the books for NEET. I would prefer you buying books and reading. Rather choosing any online portal. As you have vast data online. And makes it difficult to choose preferred sites. Yet there are some useful YouTube channels like the

1. Khan Academy

2. Exam Fear

3. Aakash iTutor

4. mLearning India

5. Etoos Education

Hope this helps you. All the best.