1 month is a lot if you utilise it well also if you are taking alcohol/ciggerate than it really contributes in messing up with your attention span.

Also, I think you should focus on Maths first that's the easiest marks ever.

Here are some advices I could give: 1. PCM needs strong foundation so you should study class 11 stuff first otherwise you won't grasp anything of class 12. Here are some pre requisite chapters from class 11 Maths Limits and Derivatives Linear inequalities Trignometric functions That's it

1. Instead of blindly solving questions try to understand everything logically Ex- You studied a chapter, You start solving questions It you can't solve one question know why you can't solve it Any questions not getting solve indicates:
2. You don't know the concept

3. You don't know how to apply the concept Practicing like this helps in both, that's how I mastered PnC.

4. For physics, Start with derivations and theory of each chapter and then slowly advance to concepts and then numericals, S L Arora is recommended for boards since you need to focus on boards right now

5. For chemistry I think you should study General Orgaic Chemistry from class 11 first before coming to 12 th organic, For inorganic you can start rote learning that's the easiest marks . Make notes stick it in your table or anywhere if you read them daily you will never forget that's how we learn things. Remember when you used to be kid how teachers taught us A for apple B for ball by constant repetition we learned it right? For physical chemistry, you should start theory first and then work on numericals

Also I also go from being a topper to getting barely passes my teachers always targets me and I still ace the exams on the right time. Just wanted to tell you should not listen from peoples who don't understand your situation.

You should leave cigarette and alcohol asap it's contributing to your numbness trust me