Generally, in Nov-Dec month students are done with their syllabus as you have not mentioned what is your current preparation status so I am assuming you are also done with the same. And the left out time is for revision and for that purpose sample papers and previous year papers are the best sources so better to focus on that because this will help you to learn all important questions and once you are done with these, start doing online mocks as well. Also, for physics better to make all your concepts strong and for that practice is really must.

Good Luck!!!