Yes I was in the same situation in my 12th standard as well as my repeat year. I'll guide you. In my 12th grades, I found that chapter very tough to solve something I decided to skip it and when I was in my repeat year, obviously I was double the dedicated so I finished that chapter and trust me it was my strength. If you read the theory well, understand the concept well, believe me, chapter is damn easy, solving tricky mcqs is also quite easy. But yes if you are unable only to understand things of this chapter,  then better to leave that chapter and focus on other things... Because it's like either you run for that 1 or 2 questions to be asked from this chapter or leave them straight away and try to catch the others. Know where you stand and then choose accordingly that if you leave this chapter, then there are backup chapters ready for you or not.

Best wishes. Thank you.