HELP NEEDED phy wayyy too hard

Jus finished my 10 boards started prep for 11 with phy chap 1 units and measurement. I understood it but the mf questions yall I search up units and measurements pyq neet can't understand 1 questions like tf [ planck law we didn't even learn tf that is it's in the question angular momentum like we don't learn it in the chap how tf do I do this chapter ?