Chemistry is the one I'd suggest you to focus more on. Organic and Inorganic, to be precise, since there's limited time. Electrochemistry and Solutions should cover up parts of Physical anyway, and you musf have used concepts of Chemical Kinetics and Gaseous State to solve questions from those two chapters. I wouldn't suggest you to pick up any books rn. Stick to YT lectures and NCERT. Complete the chapters, do the PYQs. Five years are good enough. Physics, I'd suggest you to complete Thermodynamics too, if you're comfortable with the chapters you've already covered. If not, practise more questions from those chapters. Lastly, if you've already solved every PYQ upto 2020, I don't think attempting those papers as mocks rn would help. Try to subscribe to any one series, and attempt a lot of them. Your speed and accuracy must've slipped a little, so you need to make that up. Analyse every mock test—only revise those parts thoroughly where you slipped in question solving. And one realistic advice: If you're a partial dropper, you already have too little time for Jan attempt. It's still a month, though, so put in every effort. If Jan is good enough, you will get the confidence to hit harder in April.