gud morning,

Sure , you can get 150+ or more in 40 days preparation.i'm gonna assume that you're aware of syllabus,pattern.then what you have to do is first put schedule for chemistry.try to solve NCERT book questions and previous paper questions.dont get tensed,you've 40 days so it'll be just enough for JEE Main.first chemistry then do the same preparation for physics.then for maths, in maths you've to know all the formulae . if you dont understand one method of solving, just create shortcut of your own.to know the important topics and reference books please refer below link:

https://engineering.careers360.com/download/ebooks/jee-main-preparation-tips-important-topics-and-books

apart from this, i've noticed you were asked about MHT CET for COEP.first decide what you gonna prepare for -is it for MHTCET/JEE.because for COEP both marks will be considered.

I Hope this information will be useful to you.

if you need additional information,let us know to help you.

Thank you!!!:)