The questions of OJEE B.Pharma will be asked from Physics, Chemistry, Biology or Mathematics of +2 science, Each topic is important to study for the exam to score good marks in the exam, so I would suggest you to complete whole the syllabus. You can check the syllabus with the given below link.

https://odishajee.com/important_doc/syllabus2019_38.pdf

Good Luck!