Hello there!

Greetings!

If you are getting bored then first of all don't sit for long hours like continously 4-5 hours,  study in small sessions like you should take break of around 10-15 minutes after every 1.5 hours . Also keep changing the topic you are studying.  For example, if you are reading and memorising something in Inorganic , then after studying it for 1.5 hours you should take a break and then start solving numericals in physical chemistry.  Also , you can easily cover the whole syllabus of class 11 and 12 with the help of Chemistry videos on youtube. 1st complete a chapter from videos and then from book and trust me you will enjoy learning chemistry.

Thankyou